Question

PLease help.
Jim wants to react hydrogen and oxygen to get 36 grams of water.

If he starts with 4 grams of Hydrogen (H), then how many grams of Oxygen does he need for the reaction? _____________ grams

Answer 1

no of moles in 4 grams of H2=4/2=2

2H2+O2............2H2O

the reaction shows that 2 moles of H2 react with 1 mole of O2 to produced 2 moles H2O

now no of moles in  36grams of H2O=36/18=2

therefore he needed 1 mole of O2 to produce 36 grams of H2O and 1 mole of  oxygen is equal to 32 grams of O2