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A1- Chemistry Mcqs paper Time 1 hour

1. In the radioactive decay of an isotope of lead to an isotope of bismuth, a particle

0

1X is emitted. Which particle is 0

1X ?

A electron B ion C neutron D proton

2. As a simplification, an adult human can be considered to have a daily diet of 1.80 kg of carbohydrate(empirical formula CH2O).Which mass of carbon dioxide does a person produce each day if all the carbohydrate eaten is digested and oxidised?

A 0.267 kg B 0.800 kg C 1.32 kg D 2.64 kg

3. The diagram shows the mass spectrum of a sample of naturally-occurring copper.

What is the relative atomic mass of this copper?A 63.3 B 63.5 C 63.6 D 64.0

4. The use of the Data Booklet is relevant to this question.What is the number of molecules in 500 cm

3of oxygen under room conditions?

A 1.25 x 1022

B 1.34 x 1022

C 3.0 x 1022

D 3.0 x 1026

5. In the preparation of soft margarine, glyceryl trieleostearate

is suitably hydrogenated so that, on average, one of its side-chains is converted into theCH3(CH2)4CH=CHCH2CH=CH(CH2)7CO2 residue and two side-chains are converted into theCH3(CH2)7CH=CH(CH2)7CO2 residue.How many moles of hydrogen are required to convert one mole of glyceryl trieleostearate into the soft margarine?

A 4 B 5 C 6 D 9

6. Which of these samples of gas contains the same number of atoms as 1g of hydrogen (Mr : H2, 2)?A 22 g of carbon dioxide (Mr : CO2, 44)B 8 g of methane (Mr : CH4, 16)C 20 g of neon (Mr : Ne, 20)D 8 g of ozone (Mr : O3, 48)

7.Self-igniting flares contain Mg3P2. With water this produces diphosphane, P2H4, which is spontaneously flammable in air.Which equation that includes the formation of diphosphane is balanced?

A Mg3P2+ 6H2O3Mg(OH)2+ P2H4B Mg3P2+ 6H2O3Mg(OH)2+ P2H4+ H2C 2Mg3P2+ 12H2O6Mg(OH)2+ P2H4+ 2PH3D 2Mg3P2+ 12H2O6Mg(OH)2+ 3P2H4

8.Use of the Data Booklet is relevant to this question. Most modern cars are fitted with airbags. These work by decomposingsodium azide to liberate nitrogen gas, which inflates the bag.

2NaN33N2+ 2NaA typical drivers airbag contains 50 g of sodium azide.Calculate the volume of nitrogen this will produce at room temperature.A 9.2 dm

3 B 13.9 dm

3 C 27.7 dm

3 D 72.0 dm

3

9.A pure hydrocarbon is used in bottled gas for cooking and heating.When 10 cm

3of the hydrocarbon is burned in 70 cm

3of oxygen (an excess), the final gaseous mixture contains 30 cm

3of

carbon dioxide and 20 cm3

of unreacted oxygen. All gaseous volumes were measured under identical conditions.What is the formula of the hydrocarbon?

A C2H6 B C3H6 C C3H8 D C4H10

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10.On collision, airbags in cars inflate rapidly due to the production of nitrogen. The nitrogen is formed according to thefollowing equations.

2NaN32Na + 3N210Na + 2KNO3K2O + 5Na2O + N2

How many moles of nitrogen gas are produced from 1 mol of sodium azide, NaN3?A 1.5 B 1.6 C 3.2 D 4.0

11.What is the order of increasing energy of the listed orbitals in the atom of titanium?A 3s 3p 3d 4s B 3s 3p 4s 3d C 3s 4s 3p 3d D 4s 3s 3p 3d

12.Which of the following particles would, on losing an electron, have a half-filled set of p orbitals?

A C B N C N

D O

+

13.Gallium nitride, GaN, could revolutionise the design of electric light bulbs because only a small length used as a filamentgives excellent light at low cost. Gallium nitride is an ionic compound containing the Ga

3+ion. What is the electron arrangement

of the nitrogen ion in gallium nitride?A 1s

22s

2B 1s

22s

22p

3C 1s

22s

22p

4D 1s

22s

22p

6

14.Use of the Data Booklet is relevant to this question.The electronic structures of calcium, krypton, phosphorus and an element X are shown.Which electronic structure is that of element X?

A 1s2

2s2

2p6

3s2

3p3

B 1s2

2s2

2p6

3s2

3p6

4s2

C 1s22s

22p

63s

23p

63d

64s

2D 1s

22s

22p

63s

23p

63d

104s

24p

6

15.An atom has eight electrons. Which diagram shows the electronic configuration of this atom in its lowest energy state?

16.In which pair do both atoms have one electron only in an s orbital in their ground states?A Ca, Sc B Cu, Be C H, He D Li, Cr

17.Use of the Data Booklet is relevant to this question.Which graph represents the number of unpaired p orbital electrons for atoms with proton numbers 13 to 18?

1313

13 13

1414

14 14

1515

15 15

1616

16 16

1717

17 17

1818

18 18

proton numberproton number

proton number proton number

number ofunpairedelectrons

number ofunpairedelectrons

number ofunpairedelectrons

number ofunpairedelectrons

00

0 0

BA

C D

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26.In this question, the methyl group, CH3, is represented by Me.Trimethylamine, Me3N, reacts with boron trifluoride, BF3, to form a compound of formula Me3N.BF3.How may this reaction be written in terms of the shapes of the reactants and products?

27. The African weaver ant defends its territory by spraying an intruder with a mixture of compounds. The ease by which thesecompounds are detected by other ants depends upon the volatility, which decreases as the strength of the intermolecular forcesin the compound increases.Which compound would be the most volatile?A CH3CH2CH2CH2CH2CH3 B CH3CH2CH2CH2CH2CHOC CH3CH2CH2CH2CH2NH2 D CH3CH2CH2CH2CH2OH

28. Which of the following molecules has no permanent dipole?A CCl2F2 B CHCl3 C C2Cl4 D C2H5Cl

29. Which is the most likely shape of a molecule of hydrazine, N2H4?

30. Which of the following exists in the solid state as a giant covalent lattice?A ice B iodine C silicon(IV) oxide D tin(IV) chloride

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SECTION B

31.Which pairs of compounds contain one that is giant ionic and one that is simple molecular?1 Al2O3and Al2Cl6 2 SiO2and SiCl4 3 P4O10and PCl3

32.A quantity of solid Y was placed in a previously evacuated vessel and the apparatus was then held at a series of differenttemperatures. At each temperature, the mass of Y in the vapour state was calculated from pressure measurements. The resultsare shown below.

What can be deduced from the diagram?1 The mass of Y used in the experiment was m.2 The pressure of the vapour was constant for all temperatures above temperature T.3 Liquid appeared at temperature T.

33.An ideal gas obeys the gas laws under all conditions of temperature and pressure.Which of the following are true for an ideal gas?1 The molecules have negligible volume.2 There are no forces of attraction between molecules.3 The molecules have an average kinetic energy which is proportional to its absolute temperature.

34.The isotope cobalt-60 ( 6027Co ) is used to destroy cancer cells in the human body.

Which statements about an atom of cobalt-60 are correct?

1 It contains 33 neutrons.2 Its nucleus has a relative charge of 27+.3 It has a different number of neutrons from the atoms of other isotopes of cobalt.

35.Use of the Data Booklet is relevant to this question.The technetium99 isotope (

99Tc) is radioactive and has been found in lobsters and seaweed adjacent to nuclear fuel

reprocessing plants. Which statements are correct about an atom of99

Tc?1 It has 13 more neutrons than protons.2 It has 43 protons.3 It has 99 nucleons.

36.For complete combustion, 1 mol of an organic compound X was found to require 2.5 mol of molecular oxygen.Which compounds could be X?1 C2H5OH 2 C2H2 3 CH3CHO

37.On a scale in which the mass of a12

C atom is 12 the relative molecular mass of a particular sample of chlorine is 72.Which properties of the atoms in this sample are always the same?1 radius 2 nucleon number 3 isotopic mass

38. The conversion of graphite into diamond is an endothermic reaction (H = +3 kJ mol1

).

C(graphite) C(diamond)Which statements are correct?1The enthalpy change of atomisation of diamond is smaller than that of graphite.2 The bond energy of the CC bonds in graphite is greater than that in diamond.3 The enthalpy change of combustion of diamond is greater than that of graphite.

39.Sodium ions can be formed from sodium atoms.

Na(s) Na+

(g)Which quantities are required to calculate the enthalpy change of formation of gaseous sodium ions?1 enthalpy change of atomisation of sodium2 first ionisation energy of sodium3 enthalpy change of formation of sodium

40.For which reactions does the value of Horepresent both a standard enthalpy change of combustion and a standardenthalpy change of formation?

1. C(s) + O2(g) CO2(g) 2. 2C(s) + O2(g) 2CO(g) 3. CO(g) + O2(g) CO2(g)