Answer:
The amount of Mg was enough
Explanation:
In this case, we have to start with the <u>reaction</u> between and
, so:
If we check <u>the reaction is already balanced</u>. Now, we can do some stoichiometry to calculate the amount of Mg. The first step is the number of moles of . To this we have to calculate the molar mass of
first, so:
Cu: 63.55 g/mol and O: 16 g/mol. So, (63.55+16)= 79.55 g/mol.
Now, we can calculate the moles:
The <u>molar ratio</u> between and
is 1:1, so:
.
Now we can <u>calculate the mass of M</u>g if we know the atomic mass of Mg (24.305 g/mol). So:
<u>With this in mind, the student added enough Mg to recover all the Cu.</u>
Note: The HCl doesn't take a role in the reaction. The function of HCl is to dissolve the .
I hope it helps!