Stoichiometry. Question Paper 1. Subject Chemistry (0620/0971) Cambridge International Examinations (CIE) Topic. Stoichiometry.

Transcription

1 Stoichiometry Question Paper 1 Level IGSE Subject hemistry (0620/0971) Exam oard ambridge International Examinations (IE) Topic Stoichiometry Sub-Topic Stoichiometry ooklet Question Paper 1 Time llowed: 35 minutes Score: /29 Percentage: /100 Grade oundaries: >85% 75% 68% 60% 53% 48% 40% % <25% 1

2 1 For each atom of carbon present in a molecule, there is an equal number of atoms of oxygen but twice as many atoms of hydrogen. What is the formula of the molecule? 2 2 O O O O 2 Water is formed when 48 g of oxygen combine with 6 g of hydrogen. What mass of oxygen combines with 2 g of hydrogen? 12 g 16 g 96 g 144 g 3 Nitrogen and hydrogen react together to form ammonia. N N 3 When completely converted, 7 tonnes of nitrogen gives 8.5 tonnes of ammonia. ow much nitrogen will be needed to produce 34 tonnes of ammonia? 7 tonnes 8.5 tonnes 28 tonnes 34 tonnes 4 Which relative molecular mass, M r, is not correct for the molecule given? molecule M r ammonia, N 3 17 carbon dioxide, O 2 44 methane, 4 16 oxygen, O

3 5 The chemical compositions of two substances, W and X, are given. W Nal Si 3 O 8 X a(l 2Si 2 )O 8 Which statements are correct? W and X contain the same amount of oxygen. W contains three times as much silicon as X. X contains twice as much aluminium as W. 1 and 2 1 and 3 2 and 3 1, 2 and 3 6 ydrogen and chlorine react as shown. 1 molecule of hydrogen + 1 molecule of chlorine 2 molecules of hydrogen chloride What is the equation for this reaction? 2 + 2l 2l 2 + 2l 2 l l 2 2l 2 + l 2 2 l 2 7 The relative formula mass, M r, of copper(ii) sulfate, uso 4, is 160. Which mass of sulfur is present in 160 g of copper(ii) sulfate? 16 g 32 g 64 g 128 g 8 What is the relative molecular mass (M r ) of NO 3?

4 9 compound has the formula 3 O 2. ow should the relative molecular mass, M r, of this compound be calculated? (12 + 1) + 2( ) + 1 (4 12) + (2 1) + 16 (2 12) + (4 1) + (2 16) 10 The equation for the reaction between magnesium and dilute sulfuric acid is shown. Mg + 2 SO 4 MgSO M r of MgSO 4 is 120 Which mass of magnesium sulfate will be formed if 12 g of magnesium are reacted with sulfuric acid? 5g 10 g 60 g 120 g 11 Methane, 4, burns in the air to form carbon dioxide and water. What is the balanced equation for this reaction? 4 (g) + O 2 (g) O 2 (g) O(g) 4 (g) + 2O 2 (g) O 2 (g) O(g) 4 (g) + 2O 2 (g) O 2 (g) + 2 O(g) 4 (g) + 3O 2 (g) O 2 (g) O(g) 4

5 12 The formulae of compounds W, X and Y are shown. W uso O X Y MgSO O u(no 3 ) O Which statement is correct? W contains twice as many hydrogen atoms as oxygen atoms. X contains the most oxygen atoms. Y contains the most hydrogen atoms. Y contains the same number of hydrogen and oxygen atoms. 13 Which relative molecular mass, M r, is not correct for the molecule given? molecule M r ammonia, N 3 17 carbon dioxide, O 2 44 methane, 4 16 oxygen, O compound with the formula XF 2 has a relative formula mass of 78. What is element X? argon calcium neon zirconium 15 What is the balanced chemical equation for the reaction between calcium and water? a + 2 O ao + 2 a + 2 O a(o) a O ao + 2 a O a(o)

6 16 The equation shows the reaction between magnesium and sulfuric acid. Mg + 2 SO 4 MgSO (Mg = 24, = 1, S = 32, O = 16) In this reaction, what mass of magnesium sulfate will be formed when 6 g of magnesium reacts with excess sulfuric acid? Iron forms an oxide with the formula Fe 2 O 3. What is the relative formula mass of this compound? The structure of an organic compound, X, is shown. What is the molecular formula of X? What is the relative molecular mass, M r, of nitrogen dioxide?

7 20 In athletics, banned drugs such as nandrolone have been taken illegally to improve performance. Nandrolone has the molecular formula O 2. What is the relative molecular mass, M r, of nandrolone? (Relative atomic mass: = 1; = 12; O = 16) compound contains one atom of calcium, two atoms of hydrogen and two atoms of oxygen. What is the correct chemical formula of the compound? ao 2 2 OaO 2 ao 2 a(o) 2 22 Two atoms of magnesium, Mg, react with one molecule of oxygen, O 2. What is the formula of the product? MgO MgO 2 Mg 2 O Mg 2 O 2 23 opper(ii) oxide reacts with ammonia. The left hand side of the balanced equation for this reaction is: 3uO + 2N 3 What completes the equation? 3u + 2NO 3 3u + 2N O 3u + N O 3u + 2NO O 7

8 24 What is the relative formula mass, M r, of ao 3? molecule, Z, contains two atoms of oxygen, six atoms of hydrogen and three atoms of carbon. What is the formula of Z? 3 2 O 3 O O O 2 26 luminium oxide has the formula l 2O 3. Which statement about aluminium oxide is correct? 2 g of aluminium atoms are combined with 3 g of oxygen atoms. 2 g of aluminium atoms are combined with 3 g of oxygen molecules. luminium oxide has a relative molecular mass of 102. Pure aluminium oxide contains a higher mass of oxygen than of aluminium. 27 The equation shows the reaction between magnesium and sulfuric acid. [ r :, 1; O, 16; Mg, 24; S, 32] Mg + 2 SO 4 MgSO In this reaction, which mass of magnesium sulfate is formed when 6 g of magnesium react with excess sulfuric acid?

9 28 The compound magnesium nitrate has the formula Mg(NO 3 ) 2. What is the relative formula mass of magnesium nitrate? Which quantities of chemicals will react exactly with no reactants left over? 12 g of carbon and 12 g of oxygen 12 g of carbon and 48 g of oxygen 12 g of magnesium and 16 g of oxygen 24 g of magnesium and 16 g of oxygen 9