Question

Use the following reaction to answer the question:

Zn + HCl ---> ZnCl2 + H2
2. If you start with 11.89 g of zinc, how many grams of HCl would you need to react with all of the zinc?

Answer 1

Answer:

Mass = 13.14 g

Explanation:

Given data:

Mass of zinc = 11.89 g

Mass of HCl needed = ?

Solution:

Chemical equation:

Zn + 2HCl      →     ZnCl₂ + H₂

Number of moles of Zn:

Number of moles = mass/molar mass

Number of moles = 11.89 g/ 65.38 g/mol

Number of moles = 0.18 mol

Now we will compare the moles of Zn and HCl.

               Zn        :        HCl

                1          :          2

              0.18      :      2/1×0.18 = 0.36 mol

Mass of HCl:

Mass = number of moles × molar mass

Mass = 0.36 mol ×36.5 g/mol

Mass = 13.14 g