Question

Why is water liquid at room temperature?

Answer 1

room temperature is about 20 degrees celsius 
freezing point = 0 degrees celsius
boiling point = 100 degrees celsius

thus , water is liquid at room temperature

Answer 2

At room temperature (anywhere from zero degree centigrade to 100 degrees centigrade), water is found in a liquid state. This is because of the tiny, weak hydrogen bonds which, in their billions, hold water molecules together for small fractions of a second. Water molecules are constantly on the move.