1. MCO3 heat MO + CO2

The equation above shows decomposition of a carbonate salt of metal M when it is heated. If 0.05 mole of MO had decomposed, calculate the mass of MCO3 that had decomposed. (RAM C=12, O=16, M=64).

77 soalanA 0.08 gB 1.60 gC 3.20 gD 6.40 g

( L=2 ) 2. A compound with formula X2SO4 has a relative formula mass of 174. What is the relative

atomic mass of X? (RAM O=16, S=32).

A 39B 52C 78D 104

( L=1 ) 3. 1.02 g of element X reacted with 0.8 g of oxygen to form an oxide with the empirical

formula X2O5. Determine thee relative atomic mass of element X. (O=16).

A 31B 51C 55D 56

( L=3 ) 4. Three elements are represented by the letters X, Y and Z. One atom of Z is two times

heavier than one atom of Y. One atom of Y is three times heavier than one atom of X. If the relative atomic mass of X is 31, what is the relative atomic mass of Z?

A 62B 93C 155D 186

( L=1 ) 5. Calculate the percentage mass by weight of nitrogen in urea, CO(NH2)2.

(RAM H=1, C=12, N=14, O=16)

A 10.6 %B 23.3 %C 30.4 %D 46.7 %

( L=2 )

1

6. Veronal is a barbiturate used to induce sleep in psychiatric patients. The molecular formula of veronal is C4H2N2O3(C2H5)2. Determine the relative molecular mass of veronal. (H=1, C=12, N=14, O=16)

A 160B 184C 186D 196

( L=2 ) 7. Calculate how many aluminium atoms that will have the same mass as one quinine

molecule, C20H24N2O2 (an anti-malarial drug). (H=1, C=12, N=14, O=16, Al=27).

A 12B 11C 10D 9

( L=3 ) 8. Which of the following has the most number of molecules?

(H=1, C=12, O=16, Br=80)

A 33.6 g of water, H2OB 4.0 g of methane, CH4

C 9.2 g of ethanol, C2H5OHD 13.2 g of urea, CO(NH2)2

( L=1 ) 9. Calculate the number of atoms in 2.16 g of silver.

(Ag=108, NA = 6 x 1023 mole-1)

A 1.2 x 1022

B 1.5 x 1022

C 1.2 x 1023

D 1.5 x 1023

( L=1 ) 10. Caffeine is found in coffee beans. Its molecular formula is C4H5N2O. A pill contains 0.02

mole of caffeine. Determine the mass of the compound in the pill.(H=1, C=12, N=14, O=16)

A 0.97 gB 1.62 gC 1.94 gD 2.26 g

( L=2 )

2

11. Piperazine is used to kill intestinal worms. It contains 55.8 % carbon, 11.6 % hydrogen and 32.6 % nitrogen according to the mass. Determine the empirical formula of piperazine. (H=1, C=12, N=14)

A C2H5NB C4H10N2

C C2H4ND C6H12N3

( L=2 ) 12. When 1.52 g of a metal oxide of M is reduced, 1.04 g of the metal is obtained. Determine

the empirical formula of the metal oxide. (RAM O=16, M=52).

A MO2

B M2OC M2O3

D M3O2

( L=2 ) 13. 2.40 g of metal M combines with 1.6 g of oxygen to form an oxide with the empirical

formula of MO2. Determine the relative atomic mass of M. (O=16)

A 24B 48C 52D 56

( L=3 ) 14. 10 g of calcium carbonate is added into excess hydrochloric acid. Determine the volume of

carbon dioxide gas evolved at room temperature. (C=12, O=16, ca=40, 1 mole of gas occupies a volume of 24 dm3 at r.t.p)

A 0.9 dm3

B 1.2 dm3

C 1.8 dm3

D 2.4 dm

( L=3 ) 15. A cockroach repellent has the formula of CH3(CH2)5CHCHCHO. Determine the relative

molecular mass of this substance. (H=1, C=12, O=16)

A 92B 124C 140D 278

( L=2 ) 16. Which of the following chemical equation is balanced?

3

A 2NH4Cl + Ca(OH)2 CaCl2 + 2NH3 + H2OB 2Cu(NO3)2

heat 2CuO + 4NO2 + O2

C KI + Pb(NO3)2 PbI2 + KNO3

D CuCO3 + HNO3 Cu(NO3)2 + CO2 + H2O

( L=1 ) 17. Ethene burns in air according to the equation:

C2H4 + 2O2 2CO2 + 2H2O

Calculate the mass of ethene burnt if 3.3 g of carbon dioxide is produced. (H=1, C=12)

A 0.7 gB 1.4 gC 2.1 gD 2.8 g

( L=2 ) 18. Calculate the mass of magnesium oxide formed if 4.8 g of magnesium is completely burnt

in air. (O=16, Mg=24)

A 8.0 gB 9.6 gC 12.8 gD 16.0 g

( L=2 ) 19. Copper(II) oxide reacts with nitric acid to form copper(II) nitrate and water. If 4 g of

copper(II) oxide is reacted with excess nitric acid, calculate the mass of salt formed. (N=14, O=16, Cu=64).

A 5.5 gB 6.3 gC 8.8 gD 9.4 g

( L=3 ) 20. Calcium carbonate reacts with hydrochloric acid according to the equation:

CaCO3 + 2HCl CaCl2 + H2O + CO2

If 8 g of calcium carbonate (in excess) is reacted with 0.12 mole of hydrochloric acid, determine the excess mass of calcium carbonate remaining after the reaction.(H=1, C=12, O=16, Ca=40).

A 2 gB 3 gC 5 gD 6 g

4

( L=3 ) 21. Calculate the number of molecules in 0.44 g of vitamin C, C6H8O6.

(H=1, C=12, O=16, NA = 6 x 1023 mole-1)

A 1.2 x 1021

B 1.2 x 1022

C 1.5 x 1021

D 1.5 x 1022

( L=2 ) 22. Calculate the mass of 1.2 x 1022 aspirin, C9H8O4 molecules.

(H=1, C=12, O=16, NA = 6 x 1023 mole-1)

A 1.80 gB 3.60 gC 7.20 gD 12.0 g

( L=3 ) 23. Determine the mass of one methane molecule, CH4.

(H=1, O=16, NA = 6 x 1023 mole-1)

A 1.87 x 10-21 gB 3.75 x 10-21 gC 1.87 x 10-22 gD 3.75 x 10-22 g

( L=1 ) 24. X gram of phosphorus combines with 8.0 g of oxygen to form an oxide with the empirical

formula of P4O10. Determine the value of x. (O=16, P=31)

A 2.48 gB 3.10 gC 6.20 gD 9.30 g

( L=3 ) 25. Which of the following gases has the heaviest mass at room temperature?

(H=1, C=12, O=16, Ne=20, S=32, 1 mole of gas occupies a volume of 24 dm3 r.t.p)

A 3 dm3 of sulphur dioxide, SO2

B 6 dm3 of nitrogen dioxideC 9 dm3 of methane, CH4

D 72 dm3 of hydrogen, H2

( L=1 ) 26. Monosodium glutamate (MSG) is a food enhancer. MSG contains 35.51 % C, 4.77 % H,

37.85 % O, 8.29 % N and 13.60 % Na. Determine the empirical formula of MSG. (H=1, C=12, N=14, O=16, Na=23)

5

A C4H8O4NNaB C4H8O4N2NaC C5H8O4N2NaD C5H8O4NNa

( L=3 ) 27. Allicin is a compound that gives garlic its characteristic odour. It contains 44.4 % C, 6.21

% H, 9.86 % O and 39.51 % S. Determine the empirical formula of allicin. (H=1, C=12, O=16, S=32)

A C6H10OS2

B C6H9OS2

C C5H10OS2

D C5H9OS2

( L=2 ) 28. Ceramic is made from aluminosilicate, Al2O3.2SiO2.2H2O. Determine the relative formula

mass of aluminosilicate. (H=1, O=16, Si=28)

A 210B 226 C 236D 258

( L=2 ) 29. Acetaminophen is a medicine used to relieve pain. Its molecular formula is C8H9NO2. An

acetaminophen tablet contains 0.0002 mole of the medicine. Calculate the mass of the medicine in the tablet. (H=1, C=12, N=14, O=16)

A 0.0151 gB 0.0250 gC 0.0302 gD 0.0604 %

( L=3 ) 30. Oxygen mask contains potassium superoxide, K2O which reacts with water and carbon

dioxide from exhaled air to produce oxygen.

4K2O + 2H2O + 4CO2 4KHCO3 + 3O2.

Calculate the volume of oxygen gas at room temperature that can be produced from 70.5 g of potassium superoxide.(O=16, K=39, 1 mole of gas occupies a volume of 24 dm3 at r.t.p).

A 18 dm3

B 12 dm3

C 9 dm3

D 6 dm3

6

( L=2 ) 31. Ethanol (C2H5OH) is an active ingredient in alcoholic drinks. It is prepared from

fermentation of glucose according to the equation:

C6H12O6 yeast 2C2H5OH + 2CO2.

Calculate the maximum mass of ethanol that can be produced from 18 g of glucose. (H=1, C=12, O=16)

A 4.6 gB 9.2 gC 13.8 gD 23.0 g

( L=2 ) 32. Cocaine, C17H21O4N is a drug. Calculate the number of cocaine molecules present in 0.606

g of the drug. (H=1, C=12, N=14, O=16, NA = 6 x 1023 mole-1)

A 1.2 x 1021 moleculeB 1.2 x 1022 moleculeC 5.0 x 1021 moleculeD 5.0 x 1022 molecule

( L=2 ) 33. The chlorophyll, C55H72NxO5Mg is responsible for the green colour in green leaves. If the

relative molecular mass of chlorophyll is 892, determine the value of x, that is, the number of oxygen atoms in the chlorophyll molecule. (H=1, C=12, N=14, O=16, 24)

A 3B 4C 5D 6

( L=3 ) 34. Methane burns in air according to the equation represented below:

CH4 + 2O2 CO2 + 2H2O

Calculate (i) the mass of water (ii) the volume of carbon dioxide formed at s.t.p if 3.2 g of methane is burnt in air.(H=1, C=12, O=16, 1 mole of gas occupies a volume of 22.4 dm3 at s.t.p)

Mass of water Volume of CO2

A 3.6 g 2.24 dm3

B 3.6 g 4.48 dm3

C 7.2 g 2.24 dm3

D 7.2 g 4.48 dm3

7

( L=3 ) 35. The relative atomic mass of two elements S and T is 51. Which of the following

statements is true concerning X and Y?

A The elements X and Y are isotopes.B Both S and T have the same number of protons.C 51 g of S and 51 g of T each contains the same number of atoms.D The atom of elements X and Y has 24 protons and 27 neutrons

( L=2 ) 36. X, Y and Z are three elements. The atom of Z is three times heavier than an atom of Y and

an atom of Y is two times heavier than an atom of X. If the relative atomic mass of Z is 204, what is the relative atomic mass of X?

A 102B 68C 51D 34

( L=1 ) 37. The number of molecules in 7 g carbon monoxide, CO is (C=12, O=16, NA = 6 x 1023

mole-1)

A 1.5 x 1023

B 3.0 x 1023

C 1.56 x 1022

D 3.0 x 1022

( L=2 ) 38. The relative formula mass of the complex ions [Cu(NH3)4]Cl2 and [Ni(H2O)6]SO4 are

(RAM H=1, C=12, N=14, O=16, S=32, Cl=35.5, Ni=59, Cu=64)

A 161 and 253B 203 and 263C 161 and 263D 203 and 253

( L=1 ) 39. The following substances contain 3 x 1022 atoms except

(RAM Ca=40, S=32, Ti=48, Cu=64, NA = 6 x 1023 mole-1)

A 2.0 g calciumB 1.6 g sulphurC 2.4 g titaniumD 3.6 g copper

( L=3 ) 40. Which of the following contains 9 x 1023 molecules ?

(RAM H=1, C=12, O=16, F=19, NA = 6 x 1023 mole-1)

8

A 21 g water, H2OB 32 g methane, CH4

C 48 g methanol, CH3OHD 72 g ethanoic acid, CH3COOH

( L=3 ) 41. If m is the number of atoms in 3 g of carbon, the number of atoms in 3 g of magnesium in

terms of m is (RAM C=12, Mg=24)

A

2

1m

B

3

1m

C 2mD 3m

( L=3 ) 42. What is the mass of one water molecule, H2O in gram?

(RAM H=1, O=16, NA = 6 x 1023 mole-1)

A 3 x 10-21 gB 3 x 10-22 gC 3 x 10-23 gD 3 x 10-24 g

( L=2 ) 43. 7.5 x 1023 molecules of a compound X have a mass of 25 g. What is the relative molecular

mass of X ? (Avogadro Number = 6 x 1023 mole-1)

A 16B 20C 24D 31

( L=3 ) 44. 1.2 x 1022 atoms of a metal have a mass of 1.3 g. What is the relative atomic mass of the

metal? (Avogadro Number = 6 x 1023 mole-1).

A 52B 64C 65D 78

( L=2 ) 45. A gas jar contains 1.25 mole of oxygen gas. What is the mass of oxygen in the gas jar?

(O=16)

A 20 g

9

B 28 gC 32 gD 40 g

( L=1 ) 46. What is the mass of carbon dioxide gas that contains the same number of molecules as 1.4

g nitrogen gas? (N=14, O=16)

A 1.1 gB 2.2 gC 3.3 gD 4.4 g

( L=2 ) 47. The structure of vitamin C is shown below:

What is the relative molecular mass of vitamin C?

A 88B 164C 168D 176

( L=2 ) 48. 20.8 g of an element M combines with 9.6 g of oxygen to form an oxide with empirical

formula of M2O3. Determine the relative atomic mass of element M.(RAM of oxygen = 16)

A 52B 56C 112D 207

( L=3 )

10

49. Sodium bicarbonate decomposes when heated according to the equation:

2NaHCO3 heat Na2CO3 + CO2 + H2O

If 42 g of sodium bicarbonate is heated, what is the volume of carbon dioxide evolved at room temperature and pressure? (H=1, C=12, O=16, Na=23, 1 mole of gas occupies a volume of 24 dm3 at rtp)

A 3 dm3

B 6 dm3

C 9 dm3

D 12 dm3 (B)

( L=2 ) 50. Reduction of iron(III) oxide by carbon is represented by the equation below:

3C + 2Fe2O3 heat 4Fe + 3CO2

What is the maximum mass of iron that can be obtained when 40 g ofiron(III) oxide is reduced? (RAM O=16, Fe=56)

A 7 gB 14 gC 21D 28 g

( L=2 ) 51. Copper(II) carbonate reacts with dilute hydrochloric acid according to the equation:

CuCO3 + 2HCl CuCl2 + CO2 + H2O

If 1200 cm3 of carbon dioxide is formed at room temperature and pressure, calculate the mass copper(II) carbonate that had reacted with the acid.(RAM C=12, O=16, Cu=64, 1 mole of gas occupies 24 dm3 at rtp)

A 0.62 gB 3.1 gC 6.2 gD 12.4 g

( L=2 ) 52. Ethane burns in air according to the equation:

2C2H6 + 7 O2 4CO2 + 6 H2O

Calculate the volume of oxygen needed at rtp for complete combustion of 7.5 g of ethane.(RAM H=1, C=12, 1 mole of gas occupies 24 dm3 at rtp)

A 14dm3

B 21 dm3

C 28 dm3

D 35 dm3

11

( L=3 ) 53. The molecular formula of aspirin is CH3COOC6H4COOH. Determine the mass of 0.002

moles of aspirin.(H=1, C=12, O=16)

A 0.09 gB 0.18 gC 0.36 gD 0.72 g

( L=2 ) 54. When 0.02 mol of a metal X reacts with excess of hydrochloric acid, 480 cm3 of hydrogen

gas is released at room temperature and pressure. Which one of the following is the correct equation for the reaction?(1 mole of gas occupies 24 dm3 at r.t.p)

A 2X + 2HCl 2XCl + H2

B 2X + 6HCl 2XCl3 + 3H2

C X + 2HCl XCl2 + 2H

D X + 2HCl XCl2 + H2

( L=2 ) 55. Silver oxide (Ag2O) decomposes to silver and oxygen when heated.

If 0.05 mole of silver oxide is heated, what is the mass of silver metal formed? (Ag=108)

A 2.70 gB 5.40 gC 10.8 gD 21.6 g

( L=2 ) 56. Silver oxide (Ag2O) decomposes to silver and oxygen when heated.

Calculate the volume of oxygen released measured at room temperature and pressure when 0.05 mole of silver oxide decomposed.(1 mole of gas occupies 24 dm3 at r.t.p)

A 0.6 dm3

B 1.2 dm3

C 2.4 dm3 D 3.6 dm3

( L=2 ) 57. 15.2 g of FeSO4 combines with 12.6 g of water to form hydrated salt. What is the formula

of the hydrated iron(II) sulphate salt?(Relative formula mass of FeSO4 = 152, H2O = 18)

12

A FeSO4.6H2OB FeSO4.7H2O C FeSO4.8H2OD FeSO4.9H2O

( L=2 ) 58. CoCl2.xH2O

heat CoCl2 + xH2O

When 47.6 g of hydrated cocalt(II) chloride is heated to expel the water of cyrstallisation, 26 g of anhydrous cobalt chloride remains. Determine the value of x. (Relative formula mass of CoCl2 = 130, H2O = 18)

A 5B 6C 7D 8

( L=3 ) 59. The relative atomic mass of chlorine is 35.5. What is the relative molecular mass of 2

moles of chlorine gas?

A 18.75 gB 35.5 gC 71 gD 142 g

( L=1 ) 60. The empirical formula of a compound is C2H4NO2. What information is required if we

want to determine its molecular formula?

A The density of the compound.B The mass of each element that combine to form the compound.C The relative molecular mass of the compound.D The relative atomic mass of each element.

( L=2 ) 61. How many moles of oxygen are required to oxidize 0.5 mole of sulphur dioxide to sulphur

trioxide ?

A 0.25B 0.5C 0.5D 1.0

( L=1 )

13

62. Fermentation of glucose produces ethanol (C2H5OH)and carbon dioxide according to the

equation

2C6H12O6 yeast 2C2H5OH + 2CO2

If 1000 g of glucose is completely fermented what is the mass of ethanol produced? (H=1, C=12, O=16).

A46

1000

180x g

Bgx46

180

1000

C462

1000

180xx g

Dgxx 462

180

1000

( L=2 ) 63. The oxide of metal M contains 60% by mass of M. What is the empirical formula of the

oxide? (RAM O=16, M=48).

A MOB M2OC MO2

D M2O3

( L=2 ) 64. A solution containing one mole of sodium hydroxide is added to a solution containing one

mole of chromium(III) chloride. The equation for the reaction is shown below:

CrCl3(aq) + 3NaOH(aq) Cr(OH)3(s) + 3NaCl(aq)

What is the number of mole of chromium(III) hydroxide precipitated?

A

3

1

B

3

2

C

2

1

D 1

( L=2 ) 65. How many moles of oxygen gas are needed for complete combustion of 2 moles of C4H10?

A 2B 5C 10

14

D 13

( L=1 ) 66. A metal nitrate has the formula of X(NO3)3. What is the formula of its sulphate salt?

A XSO4

B X2SO4 C X3(SO4)3

D X2(SO4)3

( L=1 ) 67. An element M forms oxides with formula MO, M2O3 and MO2. What are the charges of

the ions of metal M?

A +1, +2, +3B +2, +3, +4C +1, +3, +4D +2, +3, +5

( L=2 ) 68. Two hydrocarbons CxHy and CaYb contain the same percentage mass of carbon. It follows

that they have the same

A relative molecular massB number of isomersC empirical formulaD number of atoms in a molecule

( L=2 ) 69. Which of the following has the same molecular mass as CaCO3?

(Li=7, C=12, O=16, Na=23, Mg=24, Al=27, Si=28, S=32)

A Na2CO3

B MgSiO3

C Al2O3

D Li2SO4

( L=2 ) 70. Sodium bicarbonate decomposes on heating according to the equation:

2NaHCO3 Na2CO3 + CO2 + H2O

If 25.2 g of sodium bicarbonate is heated what is the mass of sodium carbonate left? (H=1, C=12, O=16, Na=23).

A 10.6 gB 15.9 gC 21.2 gD 31.8 g

15

( L=3 ) 71. Sodium bicarbonate decomposes on heating according to the equation:

2NaHCO3 Na2CO3 + CO2 + H2O

What is the volume of carbon dioxide produced at standard temperature and pressure?(1 mole of gas occupies 22.4 dm3 at s.t.p)

A 1.12 dm3

B 2.24 dm3

C 3.36 dm3

D 4.48 dm3

( L=3 ) 72. How many moles of hydrogen atoms does 3g of C2H6 contain? (H=1, C=12)

A 0.3B 0.6C 0.9D 1.2

( L=2 ) 73. An element E forms a hydride EH3, which contains 78.6% of E by mass. What is the

relative atomic mass of E? (H=1)

A 11B 24C 27D 31

( L=3 ) 74. An element M forms a carbide MC2, which contains 62.5% of M by mass. What is the

relative atomic mass of M? (C=12)

A 23B 24C 39D 40

( L=3 ) 75. 62 g of phosphorus vapour (Px) occupy the same volume as 22 g of carbon dioxide gas at

room temperature and pressure. Determine the value of x.\(C=12, O=16)

A 2B 3C 4D 5

16

( L=3 ) 76. Determine the number of molecules in 3.2 g of methane, CH4.

(H=1, C=12, NA = 6 x 1023 mole-1)

A 1.2 x 1022 molecules B 1.2 x 1023 moleculesC 1.5 x 1022 moleculesD 1.5 x 1023 molecules

( L=2 ) 77. What is the number of molecules in 6.36 g of phenolphthalein, C20H14O4.

(H=1, C=12, O=16, NA = 6 x 1023 mole-1)

A 1.2 x 1022 moleculesB 1.2 x 1023 moleculesC 1.5 x 1022 moleculesD 1.5 x 1023 molecules

( L=2 )

17