CHAPTER # 2 – CHEMICAL COMBINATIONS
CHAPTER 2
IX CHEMISTRY
2013/09/08
State the Law of Reciprocal Proportions
and explain anyone of them with the help
of an example.
CHEMICAL COMBINATIONS
TOPICS
2012/10/09
LAWS OF CHEMICAL COMBINATIONS
 Law of Conservation of Mass
 Law of Definite Proportions
 Law of Multiple Proportions
 Law of Reciprocal Proportions
TYPES OF CHEMICAL REACTION
 Decomposition Reaction
 Addition Reaction (Combination
Reaction)
 Single Displacement Reaction
 Double Displacement Reaction
 Combustion Reaction
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State the Law of Constant Composition
and explain it with one example.
2012
Define Landolt Experiment with labeled
diagram for practical verification of Law of
Conservation of Mass.
2009
State the Law of Conservation of Matter
and explain anyone of them with the
help of an example.
BALANCE THE FOLLOWING
CHEMICAL EQUATIONS
2018
Reproduce the following chemical
reactions in the form of balanced chemical
equations:
(i) Carbon monoxide reacts with oxygen
gas to form carbon dioxide.
(ii) Zinc metal reacts with hydrochloric acid
to give zinc chloride and hydrogen gas.
(iii) Potassium chlorate decomposes on
heating into potassium chloride and
oxygen gas.
2017
Δ
KClO3
N2 + H2
CH4 + O2
Δ
KClO3
NH3 + O2
ZN + HCl
Al + HCl
Sb + Cl2
S + H2SO4 (Conc.)
C2H2 + O2
NH3 + Cl2
S + H2SO4 (Conc.)
Atomic Mass
Empirical Formula
Molecular Formula
Molecular Formula Mass
Formula Mass
Mole
Avogadro Number
PAST PAPERS QUESTIONS
[2008-2018]
2016
THEORY
2015
2018/15/11/10/09/08
State the law of Multiple Proportions and
explain it with the help of an example.
2014
2018/12/08
What is a chemical reaction? Describe
Decomposition reaction and Combustion
reaction with an example of each type of
reaction.
2018
2015
State the law discovered by French
chemist Lavosier and describe Landolt's
experiment to verify the law with labeled
diagram and relevant chemical equation
also.
What is a chemical reaction? Define Single
Displacement reaction with a relevant
chemical equation.
DIRECTION
2008 – 2018
2014
KCl + O2
NH3
CO2 + H2O
KCl + O2
NO + H2O
ZnCl2 + H2
AlCl3 + H2
SbCl3
SO2 + H2O
CO2 + H2O
N2 + HCl
SO2 + H2O
Write only chemical equations of reaction
of hydrochloric acid with the following:
(i) Sodium Hydroxide
(ii) Sodium Bicarbonate
(iii) Manganese Dioxide
DEFINE
2017/16/15/12/11
2017/16/15/09/08
2017/16/11
2014/11/10/08
Avogadro's Number
Molar Mass
Empirical Formula
Mole
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786 Medicos and Bata Store, Block 17, Gulistan e Johar
1
CHAPTER # 2 – CHEMICAL COMBINATIONS
IX CHEMISTRY
2008 – 2018
Atomic Mass Number (a.m.u)
Atomic Mass
Molecular Formula
2014
2008
2008
DEFINE AND GIVE ONE EXAMPLE OF EACH WITH
BALANCED EQUATION:
2013/09
Double Displacement Reaction
2012/10/08
Single Displacement Reaction
2012/10
Decomposition Reaction
2011
Addition Reaction
2010/08
Combustion Reaction
MCQs
(1) 44 a.m.u. of CO2 is equal to its:
(A) Molar Mass
(C) Molecular Mass
(B) Atomic Mass
(D) Mass Number
(2) A formula that indicates the actual number
and type of atoms in a molecule is called:
(A) Empirical Formula
(B) Formula Mass
(C) Molecular Formula
(D) Molecular Mass
(3) It is the empirical formula of glucose:
(A) CH2O
(C) C5H10O5
(B) C2H4O2
(D) C6H12O6
(4) How many molecules are there in 18 gm of
water:
(A) 6.02x1022
(C) 6.20 x 1022
(B) 6.02 x 1023
(D) 6.20 x 1023
(5) 5 moles of water are equal to:
(A) 80 gram
(C) 100 gram
(B) 90 gram
(D) 180 gram
(6) Molecular Mass expressed in grams is called:
(A) Atomic Mass
(C) Formula Mass
(7) In
(B) Molar Mass
(D) Equivalent Mass
1785, the French chemist
presented the law of:
(A) Conservation of Mass
(B) Constant Composition
(C) Multiple Proportion
(D) Reciprocal Proportion
Lavosier
(8) A reaction in which a chemical substance
breaks down to form two or more simpler
substances is called:
(A) Decomposition Reaction
(B) Addition Reaction
(C) Displacement Reaction
(D) Combustion Reaction
DIRECTION
Shumail Arcade, Near Johar Chorangi, Adjacent Street of
786 Medicos and Bata Store, Block 17, Gulistan e Johar
2