How many moles of water are produced when 3.0 moles of hydrogen gas react with 1.8 moles of oxygen gas?

a. 3.0 moles of water
b. 3.6 moles of water
c. 5.3 moles of water
d. 7.0 moles of water

a. 3.0 moles of water

Explanation:

According to stoichiometry,

2 moles of hydrogen combine with 1 mole of oxygen.

Thus 3 moles of hydrogen combine = moles of oxygen.

Thus hydrogen is the limiting reagent as it limits the formation of product and oxygen is the excess reagent as it is present in excess. (1.8-1.5)= 0.3 moles of oxygen will be left as such.

If 2 moles of hydrogen produce = 2 moles of water

3 moles of hydrogen will produce =moles of water.