Question

a hydrogen-filled balloon was ignited and 1.60g of hydrogen reacted with 12.8g of oxygen. how many grams of water vapor were formed? (assume that water vapor is the only product.)could you help me with this one:) ?

Answer 1

2H2 + O2 ---> 2H2O

1 mole of H2 = 2g
1 mole of O2 = 32g
1 mole of H2O = 18g

according to the reaction:
2*2g H2---------------32g O2
1,6g H2----------------- x g O2
x = 12,8g O2

so reaction is stechiometric

32g O2---------------- 2*18g H2O
12,8g O2 -------------- x
x = 14,4g H2O

answer: 14,4g of water vapour