CHEMISTRY HELP!!! you can?

Question

How many grams of hydrogen will be given at dissolution 150g of zinc in hydrochloric acid

Answer 1

Assume that there is enough HCl to dissolve ALL the zinc.

Zn + 2 HCl ---> ZnCl2 + H2
moles of Zn = 150g/65.38g/mol = 2.29 moles Zn
moles of H2 = 2.29mole x (1/1) = 2.29 moles of H2 produced

mass of H2 = 2.29moles x (2 x 1.01g/mole) = 4.63g H2

Answer 2

I am assuming there is enough HCl to totally dissolve ALL the zinc.

Here's how to do this, first, get the BALANCED equation for the reaction:

Zn + 2 HCl ---> ZnCl2 + H2

Now, determine the number of moles of reactant (zinc)

150g/65.38g/mol = 2.29 moles Zn

Now, from the ratios in the balanced equation and moles of starting material, you can calculate moles of H2:

2.29mole x (1/1) = 2.29 moles of H2 produced

Now, convert to grams by multiplyiong by the molar weight for H2 (make certian to use weight of H2, NOT H!)

2.29moles x (2 x 1.01g/mole) = 4.63g H2

Note: xenoxide has the right idea, unfortunately he used the atomic number, instead of the atomic mass for zinc.

Answer 3

moles of Zinc=150g/30=5 moles of Zinc
Form an equation:Zn+2HCl->ZnCl2+H2
1 mole of Zinc(Zn) produces 1 mole of Hydrogen
therefore 5 mole of Zinc(Zn) produces 5 mole of Hydrogen
moles=mass/mr
5=mass/2
mass of hydrogen=2.5 grams

Answer 4

Need to know the volume/concentration of HCl to solve this.