So the unbalanced equation would be Mg + N^2 --> Mg^3N^2
Which means the balanced equation would be 3Mg + N^2 --> Mg^3N^2
This is balance the equation out since you now has 3 magnesium and 2 nitrogen on the left side, and 3 magnesium on 2 nitrogen on the right. Double check my work though, it's been awhile.
Answer:

Explanation:
Hello,
In this case, we can first compute the heat required for such temperature increase, considering the molar heat capacity of water (75.38 J/mol°C):

Afterwards, the mass of ice that can be melted is computed by:

So we solve for moles with the proper units handling:

Finally, with the molar mass of water we compute the mass:

Best regards.
Answer:
The pH is approximately: 2.1549
Explanation:
pH = - log(0.007)