Which metal exists in a liquid state at room temperature?

Galvanisation is a method of protecting iron from rusting by coating it with a thin layer of:

Which of the following gases is combustible?

Who discovered the method for the industrial production of ammonia?

An element $A$ is soft and can be cut with a knife. It is very reactive to air and cannot be kept open in air. It reacts vigorously with water. Identify the element from the following:

When excess water is added to sodium aluminate and stirred continuously,it undergoes hydrolysis to form white gelatinous precipitates of which substance?