0.6905kg zinc reacts with hydrochloric acid.how many balloons can be filled with the hydrogen gas where the pressure inside the balloon is 790metrehg and temperature is 27 degree centigrade .

Answer 1

Zn + 2HCl ==> H2 + ZnCl2
mols Zn = mass/atomic mass Zn. I would use 690.5/65.38 = ?
1 mol Zn = 1 mol H2; therefore,
? mols Zn = same mols H2.

When you know the size of the balloon or something about the volume of each balloon you can finish the problem.