CHEMISTRY QUESTION BANK
Name: ................................
Q1. Compare physical and chemical change. At least 3 points.
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Q2. State four signs of chemical change.
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Q3. Compare physical and chemical properties. At least 2 points.
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Q4. Identify the following changes as physical or chemical changes giving scientific reason.
S.N. Examples of Change
1
Boiling water
2
Milk changing to yoghurt
3
Burning of wax
4
Sublimation of naphthalene balls
5
Turning copper into wire
Physical/chemical
change
Scientific reason
1
6
Tearing of paper
7
Bread becomes toast
8
Combustion of in petrol in a
car
9
Turning a ball of dough to
chapati
10
Digesting food
Q5. Explain what each of these properties means. State one example of a material for each property.
i.
Ductile
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ii.
Malleable
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iii.
Conductor of heat or electricity
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iv.
Insulator
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Q6. Compare elements and compounds. Write at least two points.
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Q7. Compare mixtures and compounds. Write at least three points.
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Q8. Work out the total number of atoms in each molecule of element/compound.
S.N.
Molecules
1
Al2O3
2
Fe3O4
3
Na2S04
4
H3P04
5
Mg(OH)2
Total
number of
atoms
6
C2H5COOH
Q9. Common salt (sodium chloride) and sugar are examples of compounds. When they mixed, it is
called as mixture. Explain giving scientific reasons.
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Q10. Iron and sulphur are elements and when they combine a compound, iron sulphide is formed.
Explain giving scientific reasons.
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Q11. Complete the table given below:
S.N.
Formula of
substance
1
Al2SO4
2
LiNO3
3
MgCO3
Elements present
Symbol Name
Number of
atoms
Total number
of atoms
Q12. Outline the terms:
i. Homogeneous
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ii. Heterogeneous
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iii. Pure substance
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iv. Impure substance
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