Year 11 Metals Practice Quiz 1 Solution
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1. Which metals were used before 750BC? Multiple Choice: 1 mark each
a) Cu, Al, Fe, Cr, U, W.
b) Sn, Cu, Li, Na, Ca, Ni.
c) H2O, CaCO3, CH3COOH, C2H5OH, CO2, O2.
d) Au, Ag, Cu, Fe, Pb, Sn, Hg.
2. Aluminium makes up 8.1% of the Earth’s crust on average. Why was aluminium metal first produced in the
year 1825 when copper, which is much less common in the earth’s crust was first produced over 6000 years
ago? 2 marks
Copper metal exists as sulfide ores from which copper can be produced by smelting them in an open
furnace in the presence of charcoal (obtained by burning wood). Aluminium requires electricity to
produce, but humans only learned how to generate electricity in 1800.
3. Name 5 common alloys and what they are made of:
5 marks
Alloy
Made of
Bronze
Cu and Sn
Brass
Cu and Zn
Steel
Fe and C
Solder
Pb and Sn
Stainless steel
Fe, C, Cr and Ni
4. What are the two types of alloys?
1 mark
Homogeneous (a.k.a. substitutional) and heterogeneous (a.k.a. interstitial)
5. Rank group 1 (alkali metals), group 2 (alkaline earth metals), group 3, and transition metals in order of
increasing reactivity.
1 mark
Increasing Reactivity
transition metals, group 3, Group 2 (alkaline earth metals), group 1 (alkali metals)
6. Which of the following best represents Gay-Lussac’s Law?
a) Gas volume increases with increasing temperature and decreases with increasing pressure.
b) Equal volumes of gases at the same temperature and pressure contain equal numbers of particles.
c) The acceleration of particles is proportional to the force applied and inversely proportional to their mass.
d) Volumes of gases in chemical reactions show simple whole number ratios to each other.
7. Describe the trend in atomic radius across a period?
Atomic radius decreases across a period (from left to right).
2 marks
8. Explain why the atomic radius increases down the group. Moving down a group means:
a) the atoms are getting heavier and therefore bigger.
b) an extra electron shell is added.
c) the number of electrons is increased, and between the electrons is a lot of empty space.
d) the nucleus is more unstable and therefore more prone to swelling.
9. What are the trends for ionisation energy in the periodic table?
a) Ionisation energy increases across groups and increases down periods.
b) There are no trends in ionisation energy. It is totally random.
c) The trend for ionisation energy is the opposite of the trend for electronegativity.
d) Ionisation energy increases across periods and decreases down groups.
10. How did Dmitri Mendeleev arrange the elements in his periodic table?
2 marks
He arranged them in order of increasing atomic weight. He put them into columns based on chemical
and physical properties and left gaps for elements were yet to be discovered.
11. Chlorine-bromine-iodine, lithium-sodium-potassium, and sulphur-selenium-tellurium are three examples of
Dobereiner’s triads. Give two properties of a Dobereiner triad. 1 mark
● Density of middle element triad is in between the density of first and last element in the triad.
● Atomic weight of middle element in the triad is close to the average of the molecular weights of the
first and last elements in the triad.
12. Which statement about ionisation energy is true?
a) A big jump in ionisation energy indicates the element is a non-metal.
b) The first ionisation energy of an element is always smallest.
c) Hydrogen has the highest first ionisation energy of all the elements.
d) The first ionisation of sodium is greater than the first ionisation energy of potassium.
13. What is Avogadro’s number?
a) 6.022 x 1023. It was named in his honour because his work proved the relationship between the
volume of a sample of gas and the number of particles in the gas.
b) 6.022 x 1023. Avogadro proved that one mole of any substance contains 6.022 x 1023 particles.
c) 6.022 x 1023. Avogadro proved that one gram of any substance contains 6.022 x 1023 particles.
d) 6.022 x 1023. Avogadro proved that one ounce of any substance contains 6.022 x 1023 particles.
14. Rank calcium, phosphorous, fluorine in order of increasing atomic radius from smallest to largest.

Fluorine, Phosphorous, Calcium
15. Which of the following is a solubility rule?
a) All chlorides are soluble.
b) All ionic substances are soluble in water.
c) Most sulfates are insoluble in water.
d) Most sulfates are soluble in water.
3 marks
16. What is the volume of gas produced at 0°C and 100kPa when 1.000 kg of calcium carbonate is thermally
decomposed?
3 marks
CaCO3 (s) → CaO (s) + CO2 (g)
nCaCO3 = mCaCO3/MCaCO3 = 1000 ÷ (40.08+12.01+3x16.00) = 9.991 moles
nCO2=nCaCO3 = 9.991 moles
volume of CO2 = 9.991 moles x 22.71 L/mol = 226.9 L
17. Which scientist is most associated with experimentally determining the atomic weights of elements?
a) Albert Einstein.
b) Galileo Galilei.
c) John Dalton.
d) James Watt.
18. How many moles are in 27g of water?
a) Exactly 27 moles.
b) 27 x Avogadro’s number of moles.
c) Approximately 1.5 moles.
d) The number of moles cannot be determined.
19. What is the molecular weight of ammonium nitrate?
2 marks
NH4NO3: 4x14.01+4x1.008+3x16=108.072
20. What is the mass of water formed when 19.832 litres of hydrogen is reacted with 37.185 litres of oxygen at
25°C and 100kPa?
3 marks
H2 (g) + ½O2 (g) → H2O (g)
OR
2H2 (g) + O2 (g) → 2H2O (g)
nH2 = 19.832/24.79=0.8
nO2 = 33.6/24.79=1.5
From the balanced equation, twice as much hydrogen as oxygen is required but the ratio of hydrogen to
oxygen present is less than 2:1, so hydrogen is the limiting reagent.
From the balanced equation: Moles of H2O = moles of H2 = 0.8
n = m/M
m = nM = 0.8 x (1.008x2+16.00) = 14.41 grams
21. What volume of oxygen at 25°C and 100kPa would be required to completely combust 12 litres of
cyclohexane vapour at 25°C and 100kPa?
2 marks
Because all gas volumes are measured at the same temperature and pressure, we can use Avogadro’s law.
C6H12 (g) + 9O2 (g) → 6CO2 (g) + 6H2O (g)
From the balanced equation: 12 litres of gaseous cyclohexane requires 9x12 = 108 litres of oxygen.
22. Which has the greatest number of atoms present, 47g of aluminium or 20g of glucose (C6H12O6)?
n=m/M nAl = 47÷26.98 = 1.742 moles
nglucose = 20÷(6x12.01+12x1.008+6x16.00) = 0.111 moles
number of moles of atoms in 20g of glucose = 0.111 x (6+12+6) = 2.66 moles
20g of glucose has more atoms present than 47 g of aluminium
2 marks
23. What is meant by the empirical formula of a compound?
2 marks
The empirical formula of a compound is the composition of atoms or ions expressed as a simple
whole number ratio. e.g. glucose (C6H12O6 has an empirical formula of CH2O). The formula of salts
is always an empirical formula.
24. A sample of a gaseous hydrocarbon (compound containing carbon and hydrogen only) was burnt in excess
oxygen and yielded 338g of CO2 and 69g of H2O. What is the empirical formula of the hydrocarbon?
2 marks
n=m/M nCO2 = mCO2 / MCO2 = 338/(12.01+2x16.00) = 7.68 mol nC = nCO2 = 7.68 mol
nH2O = mH2O / MH2O = 69/(1.008x2+16.00) = 3.83 mol
nH = 2xnH2O = 7.66 mol
𝒏𝑪 : 𝒏𝑯 = 𝟕. 𝟔𝟖: 𝟕. 𝟔𝟔 ≅ 𝟏: 𝟏 The empirical formula is CH.
25. What mass of fuel was burnt in the above question?
n=m/M
2 marks
m=nM
mfuel = mC + mH = nC x MC + nH x MH = 7.68x12.01 + 7.66x1.008 = 92.2 + 7.72 = 99.9g
26. What does smelting mean?
a) Heating metal oxides with carbon to produce the metal.
b) Recycling aluminium.
c) Melting odorous compounds.
d) Sunning.
27. How much energy does melting and recycling aluminium cans use compared to producing aluminium from
its ore?
a) 20%.
b) 50%.
c) 5%.
d) 120%.
28. Which of the following are the main copper ores found in Australia?
a) Haematite, rutile, boehmite, and magnetite.
b) Uranite, cassiterite, ilemnite and bauxite.
c) Galena, dolomite, pentlandite and sphalerite.
d) Chalcopyrite, bornite, covellite, chalcocite, and cuprite.
29. What type of resource is petroleum?
a) A renewable resource.
b) A non-renewable resource.
c) A fossil resource.
d) A ductile resource
30. Which separation technique would be best for separating steel from scrap aluminium?
a) Magnetic separation.
b) Filtration.
c) Froth flotation.
d) Chromatography.