General Chemistry Interview Question:

When a glass rod is heated gradually and suddenly dipped in cold water, it cracks. What is the reason?? When a cool glass rod is suddenly heated, it cracks. Why?

Submitted by: Administrator

When a glass rod is heated the molecules gains etnergy and
they will be in random motion. when it is suddenly dipped
in cold water, the glass molecules contact with water
gives its energy to the lower enrgy water molecule while
the molecules inside the glass with higher energy will
relese the energy randomly as a result it creates cracks
for more surface area, so that more energy can flow in
lower time.

Same thing happens when it cooled rod is heated.
Submitted by: Administrator