What is the number of moles of hydrogen that is needed to produce 0.253 mol of water

Consider the story you just read. all but one of the choices below indicate that something is living.

The volume of a single vanadium atom is 9.29×10-24 cm3. what is the volume of a vanadium atom in microliters?

Nitric acid can be formed in two steps from the atmospheric gases nitrogen and oxygen, plus hydrogen prepared by reforming natural gas. in the first step, nitrogen and hydrogen react to form ammonia: (g) (g) (g) in the second step, ammonia and oxygen react to form nitric acid and water: (g) (g) (g) (g) calculate the net change in enthalpy for the formation of one mole of nitric acid from nitrogen, hydrogen and oxygen from these reactions. round your answer to the nearest .