Question

Given the balanced reaction: Zn + 2HCl H2 + ZnCl2 How many grams of zinc are needed to produce 5 grams of H2?

Answer 1

Answer:

$161.9gZn$

Explanation:

Hello there!

In this case, according the given balanced chemical reaction:

$Zn + 2HCl\rightarrow H_2 + ZnCl_2$

It is possible to evidence the 1:1 mole ratio of hydrogen (molar mass = 2.02 g/mol) to zinc (atomic mass = 65.41 g/mol) which is used to calculate the grams of the latter needed for the production of 5 grams of the former via stoichiometry:

$5gH_2*\frac{1molH_2}{2.02gH_2}*\frac{1molZn}{1molH_2} *\frac{65.41gZn}{1molZn}\\\\=161.9gZn$

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