Question

While lighting a candle, Paheli observed the following changes:
(i) Wax was melting.
(ii) Candle was burning.
(iii) Size of the candle was reduced.
(iv) Melted wax was getting solidified.
Of the above, the changes that can be reversed are

• A. (i) and (ii)
• B. (ii) and (iii)
• C. (iii) and (iv)
• D. (i) and (iv)

Answer 1

The correct option is D (i) and (iv)

During lighting a candle changes observed are:

• Molten wax solidifies and the solid wax can be melted again.
• Size of the candle decreases, and this cannot be reversed

Hence, melting of wax and its solidification are reversible changes.