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!
<span>To work out the volume of something from its density, use the compound measures triangle: mass over density and volume. To find volume that the beaker holds, divide the mass by the density. V = (388.15 - 39.09)/1. V = 349.06g/cm3. To find the weight of the beaker and the contents, first work out the weight (mass) of the mercury, with this formula: mass = d x v. M = 13.5 x 349.06. M = 4712.31. Then add on the weight of the beaker (39.09g). The total weight is 4751.40g.</span>
<span>The hardest known mineral is diamond.
</span>