NAME: ____________________________ CLASS: __________
Chemistry 2015
YEAR 11
HALF-YEARLY EXAM
GENERAL INSTRUCTIONS
 This exam is based on the first four sections of the ‘The Chemical Earth’ topic.
 Attempt ALL questions
 Working time – 1 hour (no separate reading time)
 Write your name on your question and answer papers.
 You will require a calculator for this exam.
 Write all answers in the spaces provided in the answer booklet using a blue or black pen.
 Draw diagrams using pencil.
 Anything written in the question book will not be marked.
 If you require scrap paper for working ask your supervising teacher.
 A copy of the Periodic Table of the Elements and Data Sheet is supplied.
Total Marks = 55
PART A MULTIPLE CHOICE (15 marks)
Allow about 15 minutes for this part.
Select the alternative A, B, C or D that best answers the question.
Place a cross in the correct space on your answer sheet.
1. Which property are filtration and sieving based on?
(A) Difference in density
(B) Difference in solubility
(C) Difference in boiling point
(D) Difference in particle size
2. Which list gives an example of an element, a mixture and a compound, in that order?
(A) Fire, water, sodium chloride
(B) Oxygen, brass, water
(C) Magnesium, silicon dioxide, air
(D) Diamond, air, nitrogen
3. What is the general trend in melting and boiling points for metals, non-metals and semi-metals?
(A) non-metals < metals < semi-metals
(B) metals > non-metals > semi-metals
(C) non-metals < semi-metals < metals
(D) There is no general trend
4. Which letters are used to represent the first 5 electron shells of atoms?
(A) A, B, C, D and E
(B) S1, S2, S3, S4 and S5
(C) P, Q, R, S and T
(D) K, L, M, N and O
5. An isotope of carbon has 8 neutrons. What would its name be?
(A) carbon-8
(B) carbon-6
(C) carbon-14
(D) carbon-12
6. What is the chemical formula of Caesium Oxide? Refer to the Periodic Table.
(A) CsO
(B) Cs2O
(C) CsO2
(D) Cs2O3
7. Both copper (II) carbonate and calcium carbonate can be thermally decomposed but calcium
carbonate decomposes at a higher temperature than copper (II) carbonate. What can be concluded
from this fact?
(A) The strength of attraction between calcium ions is greater than the strength of attraction between
carbonate ions.
(B) Calcium carbonate has a white colour but copper (II) carbonate has a green colour because
calcium carbonate is white hot while copper (II) has a lower decomposition temperature.
(C) The carbonate ions in calcium carbonate are heavier than the carbonate ions in copper (II)
carbonate.
(D) The strength of attraction between calcium ions and carbonate ions is greater than the strength of
attraction between copper (II) ions and carbonate ions.
8. Which list gives an example of a metal, a non-metal and a semi-metal, in that order?
(A) Zn, Hg, Ge
(B) Ca, H, Si
(C) He, Sb, N
(D) Fe, Ar, C
9. The thermal decomposition of a carbonate produces a gas. What test is used to test for this gas?
(A) Pop test
(B) Carbon dioxide test
(C) Limewater test
(D) Carbonate test
10. What is the name given to chemical bonds formed by sharing electrons?
(A) Covalent
(B) Ionic
(C) Metallic
(D) Isentropic
11. Which statement is true about aluminium phosphate (AlPO4)?
(A) Aluminium phosphate is a covalent compound.
(B) The valency of the aluminium ion is +3.
(C) The aluminium ion is a polyatomic ion.
(D) The aluminium ion is an anion and the phosphate ion is a cation.
12. Which of the following shows a correctly balanced equation for the reaction between magnesium
metal and hydrochloric acid?
(A) Mg + 2HCl → MgCl + H2
(B) Mg + HCl → MgCl + H
(C) 4Mg + HCl → 2Mg2Cl + H2
(D) Mg + 2HCl → MgCl2 + H2
13. Which of the following ionic equations relates to the exposure of silver halides to sunlight?
(A) Ag+ + e- → Ag
(B) Ag+ → Ag + e(C) Ag + e- → Ag+
(D) Ag → Ag+ + e14. Why was gold was discovered before aluminium?
(A) Gold is a precious metal
(B) Aluminium is more reactive than gold
(C) Aluminium is unreactive
(D) Gold is denser than aluminium
15. What happens when an ion is formed?
(A) An atom gains or loses electrons
(B) An atom gains or loses protons
(C) The atom is energised and becomes more reactive
(D) A gamma ray photon is emitted
PART B SHORT ANSWER QUESTIONS (40 marks)
Allow about 45 minutes for this part.
Write your answers in the spaces provided on your answer sheet.
Question 16 (4 marks)
Classify each of the following as chemical or physical changes.
a) Combustion of magnesium
b) Melting of ice
c) Thermal decomposition of copper (II) carbonate
d) Cracking an eggshell
Question 17 (5 marks)
Complete the table on your answer sheet.
Question 18 (4 marks)
Construct a table that identifies the physical properties of metals, non-metals and semi-metals. Include at
least two distinct (unrelated) physical properties in your table.
Question 19 (4 marks)
Construct Lewis dot (Lewis electron dot) diagrams of Ca, S2-, Na+ and N2.
Question 20 (4 marks)
Refer to the following table of crude oil fractions and answer the questions below.
Fraction
Refinery Gas
Petrol
Naphtha
Kerosene
Diesel Oil
Lubricating Oil
Fuel Oil
Greases and Wax
Bitumen
Carbon atoms
1 to 4
5 to 8
7 to 13
11 to 16
15 to 18
16 to 25
20 to 27
25 to 30
above 40
Boiling Point (°C)
below 30
30 to 125
90 to 220
175 to 275
260 to 340
350 to 400
370 to 450
400 to 500
above 500
Uses
LPG (fuel for taxis and bottled gas for BBQs)
Fuel for cars
Solvents. Also cracked to make smaller molecules
Fuel for aircraft
Fuel for heavy vehicles such as trucks
Lubricant for engines and machines
Fuel for ships and for heating (boilers)
Lubricants and candles
Road surfaces
a) Identify the number of carbon atoms in molecules of the petrol fraction.
(1 mark)
b) Describe the separation technique used to separate crude oil into its various fractions.
(3 marks)
Question 21 (1 mark)
Describe the bonding in ionic compounds.
Question 22 (5 marks)
Identify the description below that best matches each word given on your answer sheet.
Description no.
1
2
3
4
5
6
7
8
9
10
Description
a substance that consists only of atoms of the same type
decomposing a compound into simpler substances using electricity
the regions of the surface and atmosphere of a planet occupied by living organisms
a substance that consists of two or more different atoms or ions chemically bonded to each other
a positively charged ion
an ionic compound containing monatomic group 7 ions
the rigid outer part of the earth, consisting of the crust and upper mantle
a chemical reaction in which one substance is changed into two or more other substances
a chemical reaction that produces new chemical compounds from simpler substances
a process that divides a mixture into its constituent parts
Question 23 (3 marks)
Construct a diagram of an atom of 31P. Show the position of all protons, neutrons and electrons.
Question 24 (6 marks)
A mixture was gravimetrically analysed and found to consist of 2g of sand, 0.1g of sodium chloride and
0.5g of the magnetic mineral magnetite (Fe3O4).
(a) Outline an efficient method to separate the sand from the rest of the mixture.
(1 mark)
(b) Describe steps that should be taken to ensure the validity of the method outlined above.
(1 mark)
(c) Describe a situation in which gravimetric analysis supplies useful data for industry.
(1 mark)
(d) Calculate the percentage composition of each substance in the mixture by weight.
Question 25 (4 marks)
Compare and contrast the boiling and the electrolysis of water.
End of Test
(3 marks)