Page 2 - 4.Home Assignment-Physical and Chemical Change

Q8. Paheli’s mother made a concentrated sugar syrup by dissolving sugar in hot
water. On cooling, crystals of sugar got separated.
This indicates a [NCERT Exemplar]
(a) physical change that can be reversed
(b) chemical change that can be reversed
(c) physical change that cannot be reversed
(d) chemical change that cannot be reversed

Q.9. Which of the following statements is incorrect for a chemical change?
(a) Heat may be given out but never absorbed
(b) Sound may be produced
(c) A colour change may take place
(d) A gas may be evolved

Q.10.Two drops of dilute sulphuric acid were added to 1 g of copper sulphate
powder and then small amount of hot water was added to dissolve it (Step I). On
cooling, beautiful blue coloured crystals got separated (Step II). Step I and Step II
are
(a) physical and chemical changes respectively
(b) chemical and physical changes respectively
(c) both physical change
(d) both chemical change

SUBJECTIVE QUESTIONS
Sl.No Questions Mar Skill
. k

Q.1 Is cloud formation a physical change or chemical change? Explain. 1 U/E

Q.2 We should eat freshly cut apple. Why? 1 A/Av

Q.3 Write any three differences between physical and chemical change. 3 A/Av
Q.4 Magnesium ribbon bums in air and changes to white substance, i.e. 3 A/D
magnesium oxide. When magnesium oxide dissolves in water, what
type of change take place? Give reason in support of your answer.
Express the change in the form of equation.
Q.5 In addition to the formation of new products, what changes (any five)do 5 A/Av
the chemical changes accompany?