Igcse Chemistry Topic 4 Stoichiometry Ans
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Transcript of Igcse Chemistry Topic 4 Stoichiometry Ans
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IGCSE Revision Exercise (03-09) Topic 4 : Stoichiometry
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The mole
Paper 1 Oct/Nov 2009
May/Jun 2009
Oct/Nov 2006
May/Jun 2006
C
D
D
D
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IGCSE Revision Exercise (03-09) Topic 4 : Stoichiometry
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May/Jun 2005
Oct/Nov 2004
Paper 3 Oct/Nov 2008 4
D
A
7.7%
No. of mole: C: 92.3/12 = 7.69; H: 7.7/1 = 7.7 (in 100g) Simplest mole ratio: C: 7.69 / 7.69 = 1 ; H: 7.7 / 7.69 = 1 i.e. 1:1
CH
C6H6
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IGCSE Revision Exercise (03-09) Topic 4 : Stoichiometry
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Oct/Nov 2007 7b
May/Jun 2007
CaCO3 + 2HCl CO2 + H2O + CaCl2 , from the equation, HCl: CaCO3 = 2:1, so no.of mole of HCl needed is 0.006 moles, or HCl only reacts with 0.0025 moles of CaCO3
From (ii), HCl is the limiting reagent, Moles of CO2 = 0.005 x 1/2 x 24 = 0.06 dm3
BaO
B2O3
S2-
Ga3+
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IGCSE Revision Exercise (03-09) Topic 4 : Stoichiometry
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7
Oct/Nov 2006 3
86.2 x 8.84 = 762.008
762.008 / (127x2) = 3
3
40 + 12 + 3x16 = 100 * no unit
40 + 16 = 56
No. of mole of CaCO3 = no. of mole of CaO = 7000 / 56 = 125 Mass of CaCO3 = 125 x 100 = 12500 g = 12.5 kg
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IGCSE Revision Exercise (03-09) Topic 4 : Stoichiometry
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May/Jun 2006 7
4.8
0.075 0.075 0.15
1 1 2
CuFeS2
1.4 / (3x12 + 6x1) = 1.4 / 42 = 0.033
0.033
5.67 g
70.5
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IGCSE Revision Exercise (03-09) Topic 4 : Stoichiometry
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Oct/Nov 2005 1
May/Jun 2003 2
Mg2+
N3-
Mg3N2
Opposite charges / electrostatic attraction
0.24 / 24 = 0.01
0.01
0.005
0.01
0.02
0.02 dm3
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IGCSE Revision Exercise (03-09) Topic 4 : Stoichiometry
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Chemical equations
Paper 1 Oct/Nov 2009
Oct/Nov 2008
Oct/Nov 2007
B
B
B
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IGCSE Revision Exercise (03-09) Topic 4 : Stoichiometry
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May/Jun 2007
Oct/Nov 2005
Oct/Nov 2004
May/Jun 2003
D
D
C
B
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IGCSE Revision Exercise (03-09) Topic 4 : Stoichiometry
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Paper 3 Oct/Nov 2009 6
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IGCSE Revision Exercise (03-09) Topic 4 : Stoichiometry
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May/Jun 2009
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IGCSE Revision Exercise (03-09) Topic 4 : Stoichiometry
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May/Jun 2008
CuCO3 + H2SO4 CuSO4 + H2O + CO2 Or, CuCO3 + 2HCl CuCl2 + H2O + CO2 Or, CuCO3 + HNO3 Cu(NO3)2 + H2O + CO2
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IGCSE Revision Exercise (03-09) Topic 4 : Stoichiometry
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Oct/Nov 2005
0.08
0.08 x 119 = 9.52
2.48
0.08
224.48
100% x 10.4/22.48 = 46.26
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IGCSE Revision Exercise (03-09) Topic 4 : Stoichiometry
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May/Jun 2005
0.08
9.52 2.48
0.08
0.08 x 281 = 22.48 g
10.4/ 22.48 x 100 = 46.3%
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IGCSE Revision Exercise (03-09) Topic 4 : Stoichiometry
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Oct/Nov 2004 7
Paper 6 May/Jun 2003
10.0/400 = 0.025
0.025
0.025 x 160 = 4 g
0.025 x 3 = 0.075
24 x 0.075 = 1.8 dm3