September 1, 2022

Chemistry Paper 2 (233/2) 1 – (i)Sodium chloride / potassium chloride /rock salt.( 1 mark) (ii) Concentrated sulphuric (VI) acid( 1 mark) (iii) Grey solid turns green( 1 mark) ( 1 mark) (V)To avoid explosion.( 1 mark) (b) (i) I The gas reacts with silver nitrate to form insoluble silver chloride.( 1 mark) II Both gases form ammonium chloride which is white.( 1 mark) (ii)- To make hydrochloric acid.( 1 mark) – Manufacture of ammonium chloride.( 1 mark) – Manufacture of PVC.( 1 mark) – Making chloroethene /vynil chloride( 1 mark) (c)(i)imagee (ii) Presence of Ca2+ which make water hard / forms scum. ( 1 mark) 2. (i)K – Has largest atomic radius / it most readily loses its outermost electron.( 1 mark) (ii) B/N( 1 mark) (iii) D/Mg( 1 mark) (iv) A (1 ) It has the smallest/smaller atomic rad1us/ its outermost electron is more/most strongly held by nucleus.(1)( 2 mark) (v) PH is seven (7). The chlorides of group 1 elements are neutral salts.(2 marks) (b) (i) Both CaCl2 and MgCl2 have mobile ions in molten state (1) while both CCl4 and SiCl4 are molecular compounds with no mobile ions (1). (ii) Neon has molar mass of 20 While Flourine has a molar mass of 38 (l). Therefore Neon diffuses faster. (l) Since it has a lower molecular mass the faster the rate of diffusion. 3 (d) Fuel Solvent Anti-septic Manufacture of synthetic fibres Manufacture of gasohol Manufacture of ethanoic acid/vinegar Used in themometers Manufacture of other organic compounds. Any 2 (2 marks) 4. (a) -Pressure -Concentration -Catalyst -Particle size/surface area -Light intensity (1 mark) (b) (i)Draw a tangent to the graph at L12 min. (1) _ -Determine change in volume( Y) /Calculate gradlem -Determine change in time.( Y) -Divide change in volume by change in time (1) (ii)AB Low production of gas(1) while BC the rate is very high because catalyst B was added.(1) (iii) (c) (i) Lowering the temperature shifts the equilibrium to the right /favours the forward reaction. (1) Hence more S03 will be produced. (1) (ii) Platinum or Vanadium pentoxide/vanadium (v) oxide / V2O5/ platinised asbestos any (1 mark)

Chemistry Paper 1 (233/1) 1. Increasing the size of the air hole/increase the amount of air/open air holes competely. (1) 3. (a) – The anhydrous copper (II) Sulphate turns from White to blue. (1) – A grey solid is formed/droplets of a colourless liquid condense at cool pal“t.(l) (b) Reducing property.(l) 4. ~ Add soluble carbonate/Add soluble hydroxide. (1) – Filter out the zinc carbonate/filter the zinc hydroxide. (1) ~ Heat strongly the ZnCO3 to decompose it to form ZnO/Heat strongly the Zn(OH)2 to decompose it to form ZnO. (1) OR – Heat to evaporate the water. (1) – Heat ZnSO4 solid to decompose (1) to form ZnO/yellow solid. (1) 5. (a) delocalised electrons. (1) (b) ions in the melt. (1) 6. (b) Used in packaging – cushions electronics in boxes/insulation/models/ceiling strips/ crates or binding. (1) 8. (b) (i) Cobalt 60 is used to detect the activity of the thyroid gland. (1) (ii) To sterise equipment/treatment of cancer/radio active Na for disorders in blood circulation/Barium meal for ulcers/detect fractures in bones. (l) 9. The molecules of ethanoic acid interact through strong hydrogen bonding (1) forming a dimer while molecules of pentane have weak van der waals forces. (1) NB/ Ethanoic acid has hydrogen bonds while pentane does not have. 10. (a) Roast ore in air/heat in air. (l) (b) – Acid rain that corrodes stone Work on buildings/land gulleys/dust pollution. (1) – SO2 when breathed in causes bronchitis/chlorosis in plants. (1) 11. Z is SO2/ sulphur (IV) oxide. (1) M is H2SO3/ sulphuric (IV) acid. (1) 12. A(l)andD(l) A is acidic it Will neutralise Pb(OH)ZW to form salt and Water, (%) D is a strong base it Will react with Pb (OH)2W to form a complex ion. (72) Lead (II) hydroxide is amphoteric. 13. (b) Some energy is used to ionise the weak acid first before it can neutralise. So not all energy is used in neutralisation. (l) (b) It changed purple (1) The excess ammonia makes solution basic which turns purple with universal indicator. (1) 16. (a) (i) It turned brown /blue/violet/green. (1) (ii) The Water level rose up the gas jar/occupy space left by reacted O2. (1) (b) The brown colour would be more since the salt accelerates rusting/rust faster. (1) 17. (a) Rate increases. (1) (b) Temperature increases the kinetic energy (1) of the particles increasing the number of collisions. (1) 18. (a) N (l) (b) R (1) (C) M;N2 (1) 22. (a)Condensation of alcohol with higher boiling point so that it runs back to the flask as the alcohol with lower boiling point distills over. (1) (b) Methanol. (1) It has a lower boiling point due to the size of carbon chain when compared with propanol. (1) 23. (a)Step 1 is neutralisation. (1) (b) Step II is soda lime/ mixture of NaOH and CaO. (1) (c) Fuel/making ethene/making hydrogen gas. (1) 24. (a) 26. Natural polymers are biodegradable (1) and are expensive. (1) Affected by acids/Not easily recyled. 27. (a) Acetone / ethanol / propanone / propanol. (1) (b) The solvent dissolves the organic compound indicator present in the flowers / it is an organic solvent. (1) 28. (a) It absorbs carbon (IV) oxide present in the air. (1) (b) Copper /Cuts) (1) (c) It has rare noble gases which have not been removed / Argon. (1) 29. (a) A radical is a compound formed when elements combine to form ions / free unstable atoms or molecules / a group of free unstable atoms exist in a compound / group of atoms with a common charge. (1)  

Kenya certificate of Secondary Education 2016 Chemistry paper 2 Questions and Answers No. 1. Use the information in the table below to answer the questions that follow. The letters do not represent the actual symbols of the elements. (a) Give reasons why the melting point of: (i) S is higher than that of R; (1 mark) ❖ Metalic bonds in S are stronger than in R (ii) V is lower than that of U. (2 marks) ❖ V is monoatomic while U is diatomic ❖ The Van der Waals force in V are weaker than in U (b) How does the reactivity of W with Chlorine compare with that of R with chlorine? (2 marks) Explain. ❖ W reacts more vigorously ❖ It is easier to lose the odur/valence electrons in W than in T ❖ W is more electropositive than R ❖ Reactivating of groups elements. Increases down the group (c) Write an equation for the reaction between T and excess oxygen. (1 mark) ❖ 4T(s) + 502(g) -> 2T2O5(g) (d) When 1.15g of R were reacted with water, 600cm3 of gas was produced. Determine the relative atomic mass of R. (Molar gas volume = 24 000 cm2). (3 marks) (e) Give one use of element V. (1 mark) ❖ Used in florescent bulbs / lumbs ❖ Used in arc welding ❖ Used in fire extinguishers ❖ Used as a preservative in museum No. 2 .Describe the process by which Nitrogen is obtained from air on a large scale. (4 marks) ❖ Filter the air/ electrostatic precipitation/ Purify the air ❖ Pass air through NaOH in KOH to remove CO2 ❖ Cool to remove to remove water vapour ❖ Cool the remaining gases from a liquid air ❖ Perform fractural distillation of liquid air ❖ Nitrogen is collected at – 196° C (a) (b) Study the flow chart below and answer the questions that follow. (i) Identify gas J.(1 mark) ❖ Nitrogen II Oxide (NO) (ii) Using oxidation numbers, show that ammonia is the reducing agent in step Tip (2 marks) ❖ 4NH3 (g) + 3 CUO —2N2 (g) + 3H20(1) + 3 Cu ❖ Oxidation no of N in ammonia increases from -3 to 0 ❖ Oxidation number of reducing agent increases ❖ Oxidation number Cu decreases from + 2 to 0 hence an oxidizing agent Ammonia is a reducing agent (iii) Write the equation for the reaction that occurs in step (V). (1 mark) ❖ NH4NO3(s) or (ag) —>N20 (g) + 2H20 (g or 1) (iv) Give one use of ammonium nitrate. (1 mark) ❖ Fertilizer ❖ Explosive (c) The table below shows the observations made when aqueous ammonia was added to cations of elements E, F and G until in excess. Cation of Addition of a few drops of Aqueous ammonia. Addition of excess aqueous ammonia E White precipitate Insoluble F No precipitate No precipitate G White precipitate Dissolves (i) Select the cation that is likely to be Zn2+ (1 mark) ❖ G or G2+ (ii) Given that the formula of the cation of element E is E 2+ , write the ionic equation for the reaction between E2+(aq) and aqueous ammonia. (1 mark) E2+ + 20H (ag) -> E(OH)2(s) No.3.(a) Methanol is manufactured from carbon (IV) oxide and hydrogen gas according to the equation: CO2 (g) + 3H2(g) CH3OH(g) + H20(g) The reaction is carried out in the presence of a chromium catalyst at 700K and 30kPa. Under these conditions, equilibrium is reached when 2% of the carbon (IV) oxide is converted to methanol (i)How does the rate of the forward reaction compare with that of the reverse reaction when 2% of the carbon (IV) oxide is converted to methanol?(1 mk) ❖ Rate of forward reaction is equal to tare of backward reaction (ii)Explain how each of the following would affect the yield of methanol: I Reduction in pressure (2mks) ❖ Production will reduce since equilibrium will shift backward so as to raise the pressure. II Using a more efficient catalyst (2mks) ❖ No change in amount of methanol since a catalyst will help reaction to come to equilibrium (iii) If the reaction is carried out at 500K and 30IcPa, the percentage of carbon (IV) oxide converted to methanol is higher than 2% I what is the sign of ,H for the reaction? Give a reason (2mks) ❖ Negative: the reaction is exothermic since it requires low temperature to be fast. II Explain why in practice the reaction is carried out at 700K but NOT at 500K (lmk) ❖ To ensure that the reacting particles posses more activation energy (b)Hydrogen peroxide decomposes according to the following equation: 2H202(aq) ,2H20(1) + 02 (g) In an experiment, the rate of decomposition of hydrogen peroxide was found to be 6.0 x 10-8 mol dm-3 S-1. (i)Calculate the number of moles per dm3 of hydrogen peroxide that had decomposed within the first 2 minutes (2mks) ❖ No. of seconds = 2 x 60 = 120 Sec Moles of H202 decomposed = 120 x 6.0 x las = 7.20 x 106 (ii) In another experiment, the rate of decomposition was found to be 1.8 x 10 – 7 mol dm -3S-1. The difference in the two rates could have been caused by addition of a catalyst. State, giving reasons, one other factor that may have caused the difference in two rates of decomposition (2 marks) ❖ Concentration of H202 may be higher since concentration increases the rate of reaction. No.4.The set up below can be used to produce sodium hydroxide by electolysing brine. (i) Identify gas Y. (1mk) ❖ Chlorine or Cl (ii)Describe how aqueous sodium hydroxide is formed in setup above. (2mks) ❖ Na+ and H+ migrate to the cathode. The H+ ions are preferentially discharged liberating hydrogen gas. Cl– and OH- migrate to anode. The Cl+are preferentially discharged liberating Cl2 gas. Na– migrate to anode through the membrane , they combine with OH to from NaOH (iii)One of the uses of sodium hydroxide is in manufacture of soaps. State one other use of sodium hydroxide. (lmk) ❖ Glass making ❖ Separating components of

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Kenya certificate of Secondary Education 2016 Chemistry paper 1 1. A student investigated the effect of an electric current by passing it through some substances. The student used inert electrodes and connected a bulb to the circuit. The table below shows the substances used and their states. Experiment Substance State 1 Potassium carbonate Solid 2 Copper (H) sulphate Solution 3 Sugar Solution 4 Lead (II) iodide Molten (a) In which experiment did the bulb not light? (1 mark) (b) Explain your answer in (a) above. (2 marks) 2. An alkanol has the following composition by mass: hydrogen 13.5%, oxygen 21.6% and carbon 64.9%. (a) Determine the empirical formula of the alkanol. (C = 12.0, H = 1.0, 0 = 16) (2 marks) (b) Given that the empirical formula and the molecular formula of the alkanol are the same, draw the structure of the alkanol. (1 mark) 3. The figure below shows an energy cycle. (a) Give the name of the enthalpy change AI-11. (I mark) (b) Determine the value of H3. (2 marks) 4. The set up below was used to investigate the reaction between dry hydrogen gas and copper (11) oxide. (a) Name substance A. (1 mark) (b) State the observation made in the combustion tube. (1 mark) (c) Explain the observation made in (b) above. (1 mark) 5. Starting with sodium metal, describe how a sample of crystals of sodium hydrogen carbonate may be prepared. (3 marks) 6. Ammonium Ion has the following structure. Label on the structure the: (a) Covalent bond (1 mark) (b) Coordinate (dative) bond (1 mark) 7. When 8.53 g of sodium nitrate was heated in an open test tube, the mass of oxygen gas produced was 0.83 g. Given the equation of the reaction as: 2NaNO3(s) -> 2NaNO2(s) + 02(g) Calculate the percentage of sodium nitrate that was converted to sodium nitrite (Na = 23.0, N = 14.0, 0 = 16.0) (3 marks) 8. Aluminium is both malleable and ductile; (a) What is meant by? (i) Malleable (1/2 mark) (ii) Ductile(1/2 mark) (i) Malleability (1/2). mark) (ii) Ductility (1/2 mark) 9. The diagram below represents the set up that was used to prepare and collect hydrogen chloride gas in the laboratory. (a) State the purpose of concentrated sulphuric acid in the wash bottle. (1 mark) (b) Write an equation for the reaction between dry hydrogen chloride gas and heated iron. ( I mark) 10. Iron (111) oxide was found to be contaminated with copper (II) sulphate. Describe how a pure sample of iron (111) oxide can be obtained. (3 marks) 11. Complete the nuclear equation below. (a) remaining if 50 grammes 50g decayed for 40 days. (2 marks) (c) Give one harmful effect of radio isotope (1 marks) 12. During an experiment, chlorine gas was bubbled into a solution of potassium iodide. (a) State the observations made. ( 1 mark) (b) Using an ionic equation, explain why the reaction is redox. (2 marks) 13. (a) Draw the structure of compound N formed in the following reaction. (1 mark) (b) Give one use of compound N. (1 mark) 14. When fuel bums in the internal combustion engine at high temperature, one of the products formed is nitrogen (11) oxide. (a) Write the equation for the formation of nitrogen (II) oxide. (1 mark) (b) Give a reason why nitrogen (II) oxide is not formed at room temperature. (1 mark) (c) Describe how formation of nitrogen (H) oxide in the internal combustion engine leads to gaseous pollution. (2 marks) 15. Sodium hydroxide can be prepared by the following methods; I and II 1 Sodium metal -> Cold water -> sodium hydroxide + hydrogen 11 Concentrated -> Process A ->sodium hydroxide + chlorine + hydrogen Sodium chloride (a) Name one precaution that needs to be taken in method I. (1 mark) (b) Give the name of process A. (I mark) (c) Give one use of sodium hydroxide. (I mark) 16. The atomic number of sulphur is 16. Write the electron arrangement of sulphur in the following? (2 marks) (a) H2(s) (b) S032- 17. A compound whose general formula is M(OH)., reacts as shown by the equation. M(OH)3 + OH–aq -> M(OH)3 M(OH)–4 (aq)+3H–(aq) ->+M3+(aq) (a) What name is given to compounds which behave like M(01-1)3 in the two reactions. (1 mark) (b) Name two elements whose hydroxides behave like that of M. (2 marks) 18. A water trough, aqueous sodium hydroxide, burning candle, watch glass and a graduated gas jar were used in an experimental set up to determine the percentage of active part of air. Draw a labelled diagram of the set up at the end of the experiment. (3 marks) 19. In an experiment on rates of reaction, potassium carbonate was reacted with dilute sulphuric (VI) acid. (a) What would be the effect of an increase in the concentration of the acid on the rate of the reaction? (1 mark) (b) Explain why the rate of reaction is found to increase with temperature. (2 marks) 20. 60cm3 of oxygen gas diffused through a porous partition in 50 seconds. How long would it take 60cm3 sulphur (IV) oxide gas to diffuse through the same partition under the same condition? (S = 32.0, 0 = 16.0) (3 marks) 21. Draw and name the isomers of pentane. (3 marks) 22. The set up below was used to collect a dry sample of a gas. Give two reasons why the set up cannot be used to collect carbon (IV) oxide gas. (2 marks) 23. Given the following substances: wood ash, lemon juice and sodium chloride. (a) Name one commercial indicator that can be used to show whether wood ash, lemon juice and sodium chloride are acidic, basic or neutral. (1 mark) (b) Classify the substances in (a) above as acids bases or neutral. (2 marks) 24. Describe how a solid sample of potassium sulphate can be prepared starting with 200cm3 of 2M potassium hydroxide. (3 marks) 25. Charcoal is a fuel that is commonly used for cooking. When it burns it forms two oxides.

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Kenya certificate of primary Education Practical 2017 Chemistry paper 3 1. You are provided with: • Solution A, 0.5 M copper(II) sulphate • Solid B1, metal B1 powder • Solid B2, Iron powder • Solution C, 0.02 M acidified potassium manganate(VII) You are required to determine the: • Enthalpy change for the displacement reaction between metal B1 and copper(II) sulphate. • Mass of iron that reacts with copper(II) sulphate in the displacement reaction. PROCEDURE I (a) (i) Using a pipette and a pipette filler, place 25.0 cm3 of solution A into a 100 m plastic beaker. Allow to stand for about 1 minute and then measure the temperature of the solution. Record the reading in Table 1 as the initial temperature. Add al of solid B1 to the solution. Stir the mixture carefully with the thermometer an measure the highest temperature reached. This will take about 5 minutes. Recoil the reading in Table 1 as maximum temperature reached. (ii) Calculate the: I number of moles of copper(II) sulphate used. (1 mark) II enthalpy change for the reaction of metal B1 with one mole of copper(II) sulphate. (Assume that for the mixture, specific heat capacity = 4.2 Jg-‘K-1 and density = 1.0 g cm-3) (1 mark) (b) Repeat procedure I, (a) (i) with all of metal B2 (iron powder) in place of metal B1. The maximum temperature is reached after about 8 minutes. Record the temperature readings in Table 2. Retain the mixture for use in PROCEDURE II. (c) Compare the changes in temperature T1 and T2 and comment on the differences. (2 marks) PROCEDURE II (i) Fill a burette with solution C. (ii) Filter the mixture obtained in procedure I (b) into a 250 ml volumetric flask. Wash the residue with distilled water and add into the flask. Add more distilled water to make up to the mark. Label this as solution B2. (iii) Using a pipette and a pipette filler, place 25.0 cm3 of solution B2 into a 250 ml conical flask. Titrate solution B2 with solution C until a permanent pink colour just appears. Record the readings in Table 3. Repeat step (iii) and complete Table 3. (e) Calculate the average volume of solution C used (1 mark) (f) The equation for the reaction between manganate(VII) and iron(II) ions is: Mn04(aq) + 5Fe2+(aq) + 8H+(aq) > Mn2+(aq) + 5Fe3+(aq) + 4H20(aq) Calculate the number of moles of: (i) potassium manganate(VII) used. (1 mark) (ii) iron (II) ions in 25.0 cm3 solution B (1 mark) (iii) iron that reacted with copper(I1) sulphate. (1 mark) (g) Determine the mass of iron that reacted. (RAM of Fe = 55.8) (1 mark) 2. You are provided with: • Solid K • Aqueous ammonia • Aqueous sodium sulphate • Dilute nitric(V) acid • Wooden splint Solid K is suspected to be lead(II) carbonate. (a) From the reagents provided, select and describe three tests that could be carried out consecutively to confirm if solid K is lead(II) carbonate. Write the tests and expected observations in the places provided. (b) Carry out the tests described in (a) above 3. You are provided with an organic compound solid M. Carry out the following tests. Record the observations and inferences in the spaces provided. (a) Place all of solid M in a boiling tube. Add about 10 cm3 of distilled water and shake. Retain the solution for use in procedure (b) (i), (ii) and (iii). Use about 2 cm3 portions of the mixture in a test tube for tests (i), (ii) and (iii). (i) To the first portion, add all the solid sodium carbonate provided.   (ii) To the second portion, add two drops of acidified potassium manganate(VII) and warm the mixture.   (iii) To the third portion, add about 2 cm3 of acidified potassium dichromate(V1). Heat the mixture to boiling and allow to stand for about 2 minutes.    

Kenya Certificate of Secondary Education 2017 Chemistry paper 2 1. (a) Name the homologous series represented by each of the following general formulae. (i) CnH2n-2 (1 mark) (ii) CnH2n (1 mark) (b) Compound G is a triester. (i) Give the physical state of compound G at room temperature. (1 mark) (ii) G is completely hydrolysed by heating with aqueous sodium hydroxide. I Give the structural formula of the alcohol formed. (1 mark) II Write a formula for the sodium salt formed. ( I mark) III State the use of the sodium salt. (1 mark) (c) Ethyne is the first member of the alkyne family. (i) Name two reagents that can be used in the laboratory to prepare the gas. (1 mark) (ii) Write an equation for the reaction. (1 mark) (d) Perspex is an addition synthetic polymer formed from the monomer, (i) What is meant by addition polymerisation? (1 mark) (ii) Draw three repeat units of perspex. (1 mark) Give one use of perspex (1 mark) (iv) State two environmental hazards associated with synthetic polymers. (1 mark) Table 1. Use it to answer the questions that follow. (a) (i) Identify a substance that is a metal. Give a reason. (2 marks) (ii) Substance F does not conduct electricity in solid state but conducts in molten or aqueous state. Explain. (2 marks) (b) Copper(II) sulphate solution was electrolysed using the set up in Figure 1. (i) State the observations made during electrolysis. (11/2 marks) (ii) Write the equation for the reaction that occurs at the anode. (1 mark) (iii) State the expected change in pH of the electrolyte after electrolysis. (‘/2 mark) (c) The experiment was repeated using copper electrodes instead of carbon electrodes. Describe the observations made at each electrode. (1 mark) (d) Electroplating is an important industrial process. What is meant by electroplating. (1 mark) (iii) During electroplating of an iron spoon, a current of 0.6 amperes was passed through aqueous silver nitrate solution for 11/2 hours. Calculate the mass of silver that was deposited on the spoon. (3 marks) (Ag = 108.0 ; I F = 96,500 C mo1-1) 3.(a) A student used Figure 2 to investigate the action of dilute sulphuric(VI) acid on some metals. Beaker I and II contained equal volumes of dilute sulphuric(VI) acid. To beaker I, a clean iron rod was dipped and to beaker II, a clean copper rod was dipped. (i) Why was it necessary to clean the metal rods? (1 mark) (ii) Describe the observations made in each beaker. Beaker I: (1 mark) Beaker II: (1 mark) (iii) Explain the observations in (a) (ii). (2 marks) (b) Figure 3 shows the apparatus used to burn hydrogen in air. Use it to answer the questions that follow. State the role of substance X. ice-cold water Y (1 mark) (ii) Give the name of the substance that could be used as X. (1 mark) (iii) State the role of the suction pump. (1 mark) (iv) Name the product Y formed. (1 mark) (v) Give a simple physical test to prove the identity of Y. (1 mark) vi) State the difference between ‘dry’ and ‘anhydrous’. (2 marks) 4.W is a colourless aqueous solution with the following properties: I It turns blue litmus paper red. II On addition of cleaned magnesium ribbon, it gives off a gas that burns with a pop sound. III On addition of powered sodium carbonate, it gives off a gas which forms a precipitate with calcium hydroxide solution. IV When warmed with copper(II) oxide powder, a blue solution is obtained but no gas is given of V On addition of aqueous barium chloride, a white precipitate is obtained. (a) (i) State what properties (I) and (III) indicate about the nature of W. ( I mark) (ii) Give the identity of W. (l mark) (iii) Name the colourless solution formed in (II) and (III). (2 marks) (iv) Write an ionic equation for the reaction indicated in (V). ( I mark) (b) Element V conducts electricity and melts at 933K. When chlorine gas is passed over heated V, it forms a vapour that solidifies on cooling. The solid chloride dissolves in water to form an acidic solution. The chloride vapour has a relative molecular mass of 267 and contains 19.75% of V. At a higher temperature, it dissociates to a compound of relative molecular mass 133.5. When aqueous sodium hydroxide is added to the aqueous solution of the chloride, a white precipitate is formed which dissolves in excess alkali. (V = 27.0 ; CI = 35.5) (i) Determine the: I empirical formula (2 marks) II molecular formula (2 marks) (ii) Draw the structure of the chloride vapour and label the bonds. (1 mark) (iii) Write an equation for the reaction that form a white precipitate with sodium hydroxide. (1 mark) (a) When 0.048 g of magnesium was reacted with excess dilute hydrochloric acid at room temperature and pressure, 50 cm3 of hydrogen gas was collected. (Mg = 24.0; Molar gas volume = 24.0 dm3) (i) Draw a diagram of the apparatus used to carry out the experiment described above. (3 marks) (ii) Write the equation for the reaction. (1 mark) (iii) Calculate the volume of hydrogen gas produced. (2 marks) (iv) Calculate the volume of 0.1 M hydrochloric acid required to react with 0.048 g of magnesium. (3 marks) 6. The following steps were used to analyse a metal ore. (i) An ore of a metal was roasted in a stream of oxygen. A gas with a pungent smell was formed which turned acidified potassium dichromate(VI) green. (ii) The residue left after roasting was dissolved in hot dilute nitric(V) acid. Crystals were obtained from the solution. (iii) Some crystals were dried and heated. A brown acidic gas and a colourless gas were evolved and a yellow solid remained. (iv) The solid was yellow when cold. (v) The yellow solid was heated with powered charcoal. Shiny beads were formed. Name the: (a) gas formed when the ore was roasted in air. (1 mark) (b) gases

QUESTION 1 : Which of the following is NOT a method that is used to conceal inventory shrinkage? Selling merchandise without recording the sale Writing off stolen inventory as scrap Placing empty boxes on warehouse shelves Performing a forced reconciliation of the inventory records Some fraudsters try to make it appear that there are more assets present in the warehouse or stockroom than there actually are by physically padding the inventory. In one case, employees stole liquor from their stockroom and restacked the containers for the missing merchandise. This made it appear that the missing inventory was present when in fact there were really empty boxes on the stockroom shelves. Another method would be to fill boxes with bricks or other inexpensive materials and stack the boxes on warehouse shelves. One of the simplest methods for concealing shrinkage is to decrease the perpetual inventory record so that it matches the physical inventory count. This is also known as a forced reconciliation of the account. Basically, the perpetrator just changes the numbers in the perpetual inventory to make them match the amount of inventory on Writing off inventory as obsolete, damaged, or unsellable is also a relatively common way for fraudsters to remove assets from the books before or after they are stolen. This is beneficial to the fraudster because it eliminates the problem of shrinkage that inherently exists in every case of noncash asset misappropriation. Selling merchandise without recording the sale would actually increase the amount of shrinkage on a company’s books because the physical inventory would be depleted without a corresponding adjustment to the perpetual   QUESTION 2 : The person who is responsible for the shipment of inventory should also be responsible for the conversion of inventory to scrap. True False Separation of duties is among the measures commonly used to prevent inventory theft. The following duties should be handled by different personnel: Requisition of inventory Receipt of inventory Disbursement/shipment of inventory Conversion of inventory to scrap Receipt of proceeds from disposal of scrap   QUESTION 3 : An analytical review reveals that Rollins Company’s cost of goods sold increased by 80% last year. Its sales, however, only increased by 40%. What might this discrepancy indicate? Sales were unusually poor this year versus last year. There were more sales returns this year than in the prior year. Inventory has been depleted by theft. The quantity of items purchased decreased. Inventory fraud might be detected by using an analytical review because certain trends become immediately clear. For example, sales and cost of goods sold should move together since they are directly related. However, if the cost of goods sold increases by a disproportionate amount relative to sales, and no changes occur in the purchase prices, quantities purchased, or quality of products purchased, the cause of the disproportionate increase in cost of goods sold might be one of three things: (1) ending inventory has been depleted by theft, (2) someone has been embezzling money through a false billing scheme, or (3) someone has been skimming sales revenue.   QUESTION 4 : Jackson is a receiving clerk at a warehouse. His job is to count the number of units in incoming shipments, record the figures in receiving reports, and forward copies of the reports to the accounts payable department. One day, Jackson received a box of 20 laptop computers at the warehouse. His wife’s computer just broke, so he stole one of the computers from the box. To conceal his scheme, Jackson sent a receiving report to accounts payable that 20 computers arrived, but he only recorded 19 on the copy of the receiving report used for the inventory records. What A noncash larceny scheme A purchasing and receiving scheme An asset transfer scheme None of the above One of the most common examples of an employee abusing the purchasing and receiving functions occurs when a person charged with receiving goods on the victim company’s behalf—such as a warehouse supervisor or receiving clerk—falsifies the records of incoming shipments. If, for example, 1,000 units of a particular item are received, the perpetrator indicates that only 900 were received. By marking the shipment short, the perpetrator can steal the 100 The obvious problem with this kind of scheme is the fact that the receiving report does not match the vendor’s invoice, which will likely cause a problem with payment. Some employees avoid this problem by altering only one copy of the receiving report. The copy that is sent to accounts payable indicates receipt of a full shipment, so the vendor will be paid without any questions. The copy used for inventory records indicates a short shipment so that the assets on hand will equal the assets in the perpetual inventory.   QUESTION 5 : The warehouse supervisor at South Corp. has stolen $50,000 worth of inventory over the last year. He has made no effort to conceal his theft in any of the inventory records. During an analytical review of the financial statements, which of the following red flags might South Corp.’s auditors find that would indicate the inventory theft? Sales and cost of goods sold moved together. The percentage change in sales was significantly higher than the percentage change in cost of goods sold. The percentage change in cost of goods sold was significantly higher than the percentage change in sales. None of the above possible outcomes would indicate inventory theft. Inventory fraud might be detected by using an analytical review because certain trends become immediately clear. For example, sales and cost of goods sold should move together since they are directly related. However, if the cost of goods sold increases by a disproportionate amount relative to sales, and no changes occur in the purchase prices, quantities purchased, or quality of products purchased, the cause of the disproportionate increase in cost of goods sold might be one of three things: (1) ending inventory has been depleted by theft, (2) someone has been embezzling money through a false billing scheme, or (3)

QUESTION 1 : Harold, a medical provider, is compensated based on each service that he provides to patients. Which of the following best describes this method of compensation? Capitation Episode-of-care Salary Fee-for-service There are several types of reimbursements for providers: fee-for-service, capitation, episode-of-care, and salary. Each has advantages and disadvantages from an anti-fraud perspective. Fee-for-service reimbursement occurs when providers receive payment for each service rendered. The disadvantage of fee-for-service payment is that it creates an incentive for providers to increase their compensation by performing excess and unnecessary services. However, providers tend to like this payment system because it gives them wide discretion in selecting the services that meet the patient’s needs. Capitation is a reimbursement method in which providers receive one lump sum for each patient that they treat, regardless of how many services the provider renders. While this method avoids some of the incentives for providers to perform unnecessary services, it might give providers a reason to focus on the quantity of patients they see rather than the quality of service. Additionally, capitation does little to stop schemes involving fictitious patients. Episode-of-care reimbursement is a health care payment method in which providers receive one lump sum for all the services they provide related to a condition or disease (as opposed to capitation, which is a lump sum per patient). This method captures some of the benefits of capitation by removing incentives to provide unnecessary services, but it is also (in theory) more fair to providers than capitation because it compensates them more when multiple health When governments directly operate health care facilities, it is common to pay providers a basic salary rather than offer service-based compensation.   QUESTION 2 : When a medical provider performs a service for a patient but bills the patient’s health care program for a more complex and more expensive service, this practice is called upcoding. True False Upcoding occurs when a provider bills for a higher level of service than actually rendered. One common form of upcoding involves generic substitution—filling a prescription with a less expensive drug   QUESTION 3 : A health care provider’s practice of charging a comprehensive code, as well as one or more component codes, by billing separately for subcomponents of a single procedure is known as ______________. Segregating Unbundling Subdividing None of the above Because health care procedures often have special reimbursement rates for a group of procedures typically performed together (e.g., blood test panels by clinical laboratories), some providers attempt to increase profits by billing separately for procedures that are actually part of a single procedure. This process is called unbundling or coding fragmentation .   QUESTION 4 : Michael, a medical provider, performs an appendectomy, a procedure that is supposed to be billed as one code. Instead, he intentionally submits two codes for the same procedure, one for an abdominal incision and one for removal of the appendix. Which of the following best describes Michael’s scheme? Procedure compounding Decompressing Unbundling Fictitious services Because health care procedures often have special reimbursement rates for a group of procedures typically performed together (e.g., blood test panels by clinical laboratories), some providers attempt to increase profits by billing separately for procedures that are actually part of a single procedure. This process is called unbundling or coding fragmentation .   QUESTION 5 : Which of the following health care frauds would be best described as a fictitious provider scheme? A provider operates a mobile lab that bills a health care program for unnecessary tests and then relocates. A doctor at a hospital inflates the cost of his services by coding them as being more complex than they should be. A thief steals a health care provider’s identifier and bills a government health care program under the name of a fake clinic. A group of people posing as medical professionals provide services without proper licenses. In a fictitious provider scheme, corrupt providers or other criminals fraudulently obtain and use another provider’s identification information and steal or purchase lists of patient identifying information. Thereafter, the perpetrator submits bills using the fictitious provider’s information to the insurance provider or government health care program for medical services, although no services are performed.   QUESTION 6 : Falsified prescriptions for equipment, excessive supplies, noncovered supplies, and scooter scams are forms of fraud commonly involving what type of health care entity? Out-patient services groups Special care facilities Reusable medical equipment suppliers Hospitals Reusable medical equipment, often called durable medical equipment (DME), includes items such as crutches, wheelchairs, and specialized patient beds. Fraud schemes perpetrated by reusable medical equipment suppliers Falsified prescriptions for equipment or supplies Intentionally providing excessive supplies Equipment not delivered or billed before delivery Billing for equipment rental beyond when the equipment was checked out Billing for supplies not covered by the insurance policy or health care program Scooter scams (i.e., billing for electric-powered wheelchairs that are either unnecessary or are of poorer quality than the model billed for)   QUESTION 7 : A doctor provides services to both patients who pay directly and patients whose bills are paid by a government program. To make his services more attractive to patients outside the coverage of the government program, he gives patients who pay directly a discount that is not applicable to patients under the program. Which of the following best Upcoding Disparate price Fictitious claim Overutilization Many government health care programs require that they receive the best available price that providers offer. In a disparate price scheme, providers charge some patients (e.g., those in direct payment situations) a lower rate than they charge the government. This disparate bill rate causes the government to pay a higher rate in violation of regulations mandating that the government receive the lowest rate. In addition, some government health programs require that wholesale pharmacies provide the program at the average wholesale price.   QUESTION 8 : All of the following are types of medical provider fraud EXCEPT: Fictitious services Smurfing Clinical lab schemes Fictitious providers Fictitious services, clinical lab schemes,

QUESTION 1 : It is considered acceptable practice to deviate from generally accepted accounting principles (GAAP) in which of the following circumstances? It is common practice in the industry to give particular transactions a specific accounting treatment Adherence to GAAP would produce misleading results There is concern that assets or income would be overstated All of the above The question of when it is appropriate to stray from generally accepted accounting principles (GAAP) is a matter of professional judgment; there is no clear-cut set of circumstances that justify such a departure. It can be assumed that adherence to GAAP almost always results in financial statements that are fairly presented. However, the standardsetting bodies recognize that, upon occasion, there might be an unusual circumstance when the literal application of GAAP would render the financial statements misleading. In these cases, a departure from GAAP is the proper Departures from GAAP can be justified in the following circumstances: It is common practice in the entity’s industry for a transaction to be reported in a particular way. The substance of the transaction is better reflected (and, therefore, the financial statements are more fairly presented) by not strictly following GAAP. If a transaction is considered immaterial (i.e., it would not affect a decision made by a prudent reader of the financial statements), then it need not be reported. There is concern that assets or income would be overstated and expenses or liabilities would be understated (the conservatism constraint requires that when there is any doubt, one should avoid overstating assets and income or understating expenses and liabilities). The results of departure appear reasonable under the circumstances, especially when strict adherence to GAAP will produce misleading financial statements and the departure is properly disclosed.   QUESTION 2 : When looking at a set of financial statements, on which statement would you find notes payable, current assets, retained earnings, and accumulated depreciation? Statement of changes in owners’ equity Balance sheet Statement of cash flows Income statement Notes payable, current assets, retained earnings, and accumulated depreciation can all be found on the balance sheet. The balance sheet is an expansion of the accounting equation, Assets = Liabilities + Owners’ Equity . That is, it lists a company’s assets on one side and its liabilities and owners’ equity on the other side. Assets are classified as either current or noncurrent. Current assets consist of cash or other liquid assets that are expected to be converted to cash, sold, or used up, usually within a year or less. Current assets listed on the balance sheet include cash, accounts receivable, inventory, supplies, and prepaid expenses. Following the current assets are the long-term assets, or those assets that will likely not be converted to cash within one year, such as fixed assets and intangible assets. A company’s fixed assets are presented net of accumulated depreciation, an amount that represents the Liabilities are presented in order of maturity. Like current assets, current liabilities are those obligations that are expected to be paid within one year, such as accounts payable (the amount owed to vendors by a company for purchases on credit), accrued expenses (e.g., taxes payable or salaries payable), and the portion of long-term debts that will come due within the next year. Those liabilities that are not due for more than a year are listed under the heading long-term liabilities . The most common liabilities in this group are bonds, notes, and mortgages payable.   QUESTION 3 : Which of the following statements is TRUE regarding the balance sheet? The balance sheet shows the financial performance of a company over a certain period of time, such as a quarter or a year. Assets are generally presented on the balance sheet in order of liquidity. The accounts that appear on the balance sheet include revenues and expenses. Balance sheets are usually manipulated by understating assets or overstating liabilities. The balance sheet , or statement of financial position , shows a “snapshot” of a company’s financial situation at a specific point in time, generally the last day of the accounting period. The balance sheet is an expansion of the accounting equation, Assets = Liabilities + Owners’ Equity . That is, it lists a company’s assets on one side and its Assets are the resources owned by a company. Generally, assets are presented on the balance sheet in order of liquidity (i.e., how soon they are expected to be converted to cash). Generally, in a financial statement fraud scheme, the balance sheet is manipulated to appear stronger by overstating assets and/or understating liabilities.   QUESTION 4 : Debits increase asset and liability accounts. True False Entries to the left side of an account are referred to as debits, and entries to the right side of an account are referred to as credits. Debits increase asset and expense accounts, whereas credits decrease these accounts. On the other side of the equation, credits increase liabilities, revenue, and owners’ equity accounts. Conversely, debits decrease While debits do in fact increase assets, they reduce liabilities   QUESTION 5 : Chapman Inc. has always used the first-in, first-out (FIFO) inventory valuation method when calculating its cost of goods sold. This is also the standard inventory valuation method for other comparable entities in Chapman’s industry. Chapman’s controller wants to change to the weighted-average cost method because it will make Chapman’s net income appear much larger than FIFO valuation will. After several years of poor performance, management wants to boost the company’s appearance to potential investors. However, Chapman must continue to use the FIFO inventory valuation method. This is reflected in which of the qualitative characteristics of financial Comparability Going concern Relevance Valuation Users of financial statements base their decisions on comparisons between different entities and on similar information from a single entity for another reporting period. Comparability is the qualitative characteristic that enables users to identify and understand similarities and differences between such items. Consistency, although related to comparability, is not the same. Consistency refers to the use of the