Question

A tightly closed metal lid of a glass bottle can be opened more easily if it is put in hot water for some time. Explain.

Answer 1

Lid can be opened more easily if it is put in hot water for some time

Explanation:

if we put a tightly closed metal lid of a glass bottle in hot water for some time, it can be opened more easily because coefficient of expansion of metal is greater than that of glass. That's why when the metal lid comes in direct contact with hot water and metal lid expand more than the glass which in turn forms a gap between the metal lid and the glass bottle and This gap increases as the metal lid expands, due to gap the lid can be opened easily.

Answer 2

Because of Coefficient of Expansion

Explanation:

• A tightly closed metal lid of a glass bottle opens easily when dipped in hot water for certain time as metals have greater coefficient of expansion as compared to glass.  

• Hence, the lid expands at faster rate as compared to glass jar, as there is formation of gap in between  bottle & lid of metal.
• And further as the lid of metal expands so it can be opened more easily.