Question

why Squizzing lemon on a piece of rock the gas liberated turned lime water milky. which compound is present in the roc
k

Answer 1

That is a metal carbonate.
Because
Acid(present in lemon) reacts with any metal carbonate to liberate carbondioxide which further reacts with calcium hydroxide(lime water) and changes it to calcium carbonate(milky)

Hope u got that

Answer 2

Hello your answer:

When lemon is squeezed onto the rock, a gas is liberated. This gas turned the lime water milky. This confirms that Carbon dioxide is present in the rock. This is because insoluble calcium carbonate that is CaCO3 is formed.