PAPER 2

1. Mendeleev devised the modern Periodic Table. He put elements in the same Group if their
properties were similar. One of the properties he used was the formula of the oxides of the
elements. When Group I metals tarnish in air, different types of oxide are formed.

Table of Oxides

| element | oxides formed | formula |

|:---:|:---:|:---:|

| lithium | lithium oxide | Li2O |

| sodium | sodium oxide, sodium peroxide | Na2O, Na2O2 |

| potassium | potassium superoxide | KO2 |

| rubidium | rubidium superoxide | RbO2 |

(a) (i) Do the formulae of the oxides given in the table show clearly that all of the elements
belong in the same Group? Explain your answer. [1]

(ii) Do the formulae of the oxides given in the table show a trend down the Group? Explain your
answer. [1]

(b) What are the formulae of the peroxide and the superoxide ions? [2]

(c) Complete the table below to suggest the oxidation state of oxygen in each type of oxide. [3]

Oxidation State Table

| type of oxide | example | oxidation state of oxygen |

|:---:|:---:|:---:|

| oxide | Li2O | |

| peroxide | Na2O2 | |

| superoxide | KO2 | |

2. These diagrams show the electron arrangement in the outer shells of five elements, A to E. All
elements are from Period 3 of the Periodic Table.

(a) Which elements are most likely to be non-metals? [2]

(b) Which element has an atomic number of 12? [1]

(c) Which element will form three covalent bonds when it forms a compound? [1]
(d) Which two elements will form a compound with the formula of the type YZ2? [1]

3. This question is about the halogens.

(a) The table shows data about the melting and boiling points of three halogens, chlorine,
bromine and iodine. Complete the table by filling in the name of each halogen. [1]

Halogen Data Table

| name of halogen | melting point/°C | boiling point/°C |

|:---:|:---:|:---:|

| | -7.2 | 58.8 |

| | -100.9 | -34.7 |

| | 113.8 | 184.5 |

(b) Sea water contains potassium bromide.

(i) Bromine can be produced from sea water by displacement. Name an element that can
displace bromine. Give a reason for your choice. [2]

(ii) Describe a simple test, other than displacement, that can be used to show that sea water
contains iodide ions. [2]

4. The diagram shows some elements in the Periodic Table.

(a) These elements form basic oxides. [1]

(b) Atoms of this element gain two electrons when they form ions. [1]

(c) These two elements combine together to form a covalent compound with a formula of the
type XYx. [1]

(d) This element has a melting point below room temperature but a boiling point above room
temperature. [1]

(e) This element has a proton number of 19. [1]

5. Group 1 and Group VII elements show trends in their melting points and boiling points.

Table of Melting and Boiling Points

| element | melting point/°C | boiling point/°C |

|:---:|:---:|:---:|

| lithium | 180 | 1330 |

| potassium | 64 | 774 |

| chlorine | 101 | -35 |

| bromine | 7 | 59 |

| iodine | 114 | 184 |

(a) (i) The trends in melting points and boiling points for elements in Group I differ from those of
Group VII. Describe the trends down each group. [2]

(ii) The melting point and boiling point of sodium is higher than that of chlorine. Use ideas
about bonding to explain why. [3]

(b) The table shows the densities of chlorine and bromine at room temperature and pressure.

| element | density g/cm3 |

|:---:|:---:|

| chlorine | 0.03 |

| bromine | 3.12 |

A student makes a comment about the densities. 'The difference in molecular mass of chlorine
and bromine is not enough to account for the difference in densities'.

(i) Explain why the student is correct. [2]

(ii) What is the main reason that the densities of chlorine and bromine are so different? [1]

‘ATOMIC STRUCTURE AND STOICHIOMETRY

PAPER 1
1. A beam of particles contains neutrons (n), protons (p), and electrons (e). The beam is passed
through charged plates. Which diagram shows how the particles are affected by the plates?

2. The relative atomic mass of naturally occurring chlorine is not a whole number. What is the
reason for this?

A. Chlorine atoms have different numbers of neutrons.

B. Chlorine is unstable.

C. Naturally occurring chlorine cannot be obtained pure.

D. The mass of the electrons has been included.

3. Which statement about an atom is correct?

A. Each element has only one nucleon (mass) number.

B. The nucleon (mass) number can be less than the proton (atomic) number.

C. The nucleon (mass) number can equal the proton (atomic) number.

D. The number of neutrons never equals the number of electrons.

4. An isotope of element X has 40 nucleons and 19 protons. What is element X?

A. argon

B. calcium

C. cobalt

D. potassium

5. Elements X and Y have proton numbers of 3 and 11 respectively. Both elements react with
water to liberate hydrogen gas. Which statement about X and Y is not correct?

A. The chlorides of X and Y are molecular.

B. X and Y are in the same group of the Periodic Table.

C. X and Y both form basic oxides.

D. Y is more reactive with water than X.

6. Which statement is true?

A. At has more electrons than Cl.

B. Cl has more electrons than K.

D. K has more electrons than K+.

7. Which definition of isotopes is correct?1

A. Isotopes are atoms of the same element with different numbers of electrons.2

B. Isotopes are atoms of the same element with different numbers of neutrons.3

C. Isotopes are atoms with the same number of neutrons a4nd different numbers of protons.

D. Isotopes are atoms with the same physical properties and different chemical properties.

8. An element, R, has p protons and n neutrons in its nucleus. Which row gives a possible
correct number of protons, neutrons and electrons in a negative ion of an isotope of R?

Table for Isotope R Ion

| | protons | neutrons | electrons |

|:---:|:---:|:---:|:---:|

| A | p | n+1 | p |

| B | p | n+1 | p+1 |

| C | p+1 | n | p+1 |

| D | p+1 | n | p-1 |

9. Some properties of elements in the same group of the Periodic Table are listed.

1. charge on the ion

2. number of outer shell electrons

3. number of protons

4. number of inner shell electrons

Which properties show an increase as the group is descended?

A. 1 and 2

B. 1 and 3

C. 2 and 4

D. 3 and 4
PAPER 2

1. The table shows some information about atoms of the elements W, X, Y and Z.

| element | atomic number | number of protons | number of neutrons | mass number |

|:---:|:---:|:---:|:---:|:---:|:---:|

| W | 16 | 16 | 16 | 32 | 2.8.6 |

| X | 7 | 7 | 7 | 14 | 2.5 |

|Y|1|1|1|2|1|

| Z | 11 | | 12 | | |

(a) (i) Complete the table by filling in the information for element Z. [3]

(ii) Give a reason why element Z is likely to be a metal. [1]

(b) (i) Describe the change in electronic configuration that occurs to an atom of element W
when it forms an ion. [1]

(ii) The accurate relative atomic mass of element W is 32.1. Explain why this is not a whole
number. [1]

(c) Elements X and Y combine to form a covalently bonded molecule. Draw a 'dot and cross'
diagram to show the bonding in this molecule. Your diagram only needs to show outer
electrons. [2]

KINETIC PARTICLE THEORY

PAPER 1

1. Methylamine, CH3NH2 (Mr=31), and hydrogen chloride, HCl (Mr=36.5), are both gases which
are soluble in water. The gases react together to form a white solid, methylammonium chloride.
In an experiment to demonstrate rates of diffusion, the following apparatus is set up. Where will
the white solid form?

A. A

B. B

C. C

D. D
2. The graph shows the change in temperature with time when ice at −20∘C is heated to 120∘C.
Which entry in the table shows the correct change taking place between the points?

Table of Temperature Changes

| | points | change |

|:---:|:---:|:---:|

| A | P to Q | average energy of particles remains constant |

| B | Q to R | ice melting |

| C | R to S | the volume of steam is increasing |

| D | T to U | water boiling |

3. Diagrams W, X and Y show how the particles of a substance are packed at different
temperatures. The graph shows the temperature changes which occur on warming the
substance. In which region of the graph would all the 5particles be packed as in Y?

4. The apparatus can be used to show the diffusion of gases. Which pair of gases X and Y would
cause no movement of the water?

Table of Gas Pairs

||X|Y|

|:---:|:---:|:---:|

| A | C2H4 | C2H6 |

| B | C2H4 | N2 |

| C | CO2 | C2H6 |

| D | CO | NO2 |

5. The cover plate is removed from the gas jars shown in the diagram. After several days, the
colour of the gas is the same in both jars. Which statement explains this change?6

A. Oxygen and bromine gases have equal densities.7

B. Oxygen and bromine molecules8 diffuse in random motion.

C. Oxygen and bromine molecules diffuse at the same rate.

D. Equal volumes of oxygen and bromine contain equal numbers of molecules.

A. The boiling point of ammonia is less than that of hydrogen chloride.10

B. The concentration of the aqueous ammonia is less than that of the acid.11

C. The reactivity of ammonia is less than that of hydrogen chloride.12

D. The relative molecular mass of ammonia is less than that of hydrogen ch13loride.

7. The rate of diffusion of gas X (Mr=17) and gas Y (Mr=28) was compared at 25∘C and 50∘C.
Which would have the fastest rate of diffusion?

A. gas X at 25∘C

B. gas X at 50∘C

C. gas Y at 25∘C

D. gas Y at 50∘C

8. Two gases, P and Q, were separately released in a laboratory on a cold day. The experiment
was repeated on a hot day. The time taken for the gases to reach the opposite end of the
laboratory was recorded for each experiment. The relative molecular mass of gas P 14was 34
and the relative molecular mass of gas Q was 64. Which gas on which day would reach the end
of the laboratory in the shortest time?

Table of Gas Diffusion Times

| | gas | day |

|:---:|:---:|:---:|

| A | P | cold |

| B | P | hot |

| C | Q | cold |

| D | Q | hot |

PAPER 2

1. This experiment was set up to investigate the movement of gaseous ammonia and gaseous
hydrogen chloride.
(a) The white powder forms on the tube due to the reaction between gaseous ammonia and
gaseous hydrogen chloride to make solid ammonium chloride. Insert the correct symbol in the
equation to show that this reaction is reversible. [1]

(b) The tube contains two pieces of Universal Indicator paper. Complete the table to show the
colours and pH values of each piece of paper at the end of the experiment. [2]

(c) Explain why the white powder does not form in the centre of the tube. [3]

1. The table shows some information about carbon dioxide and hydrogen.

Table of Carbon Dioxide and Hydrogen Information

| gas | relative molecular mass, Mr | density in g/dm³ at room temperature and pressure |

|:---:|:---:|:---:|

| carbon dioxide | | 1.83 |

| hydrogen | | |

(a) Calculate the missing values in the table. [3]

(b) The diagram shows the start of an experiment using gas jars of hydrogen and carbon dioxide.
How will the contents of the jars change? Your answer should refer to how the amounts of
carbon dioxide and hydrogen change in the gas jars, the speed of movement of the gases in
each experiment, the reasons for each change. [4]

(c) Carbon dioxide and hydrogen can both be made by reacting solids with dilute hydrochloric
acid. Name a solid that reacts with dilute hydrochloric acid to make

(i) hydrogen, [1]

(ii) carbon dioxide. [1]

(d) Choose one of the reactions in (c) above. Write a balanced equation for the reaction. [1]