Question

How many moles of phosphoric acid would be needed to produce 15 grams of water?

Answer 1

Moles of phosphoric acid would be needed : 0.833

Further explanation

Given

15 grams of water

Required

moles of phosphoric acid

Solution

Reaction(decomposition) :

H3PO4 -> H2O + HPO3

mol water (H2O :

= mass : MW

= 15 g : 18 g/mol

= 0.833

From the equation, mol ratio H3PO4 = mol H2O = 1 : 1, so mol H3PO4 = 0.833