Metals are to the left of the zig-zag, nonmetals are to the right, and metalloids lie on/beside the line.
First identify which is being oxidized and reduced. In this case, the Mg is being oxidized and the Hg is being reduced.
Mg --> Mg+2
<span>Hg+2 --> Hg+1
</span>
Then you have to balance each half reaction first with electrons before adding them together in one equation

⇒

and

⇒
and then combine them together to form

⇒

It isn't necessary to keep the electrons but its essential to know how many there are in order to know how many are in the equation in order to calculate the reaction energy. Note: A<span>dd H+ and H2O to balance the H's and O's in acidic solution if needed.</span>
Answer:
The charge carried by each ion (oxidation state of each atom)
Explanation:
If we have an ionic compound and we want to write its formula, we must first know the magnitude of charge on each ion (shown as oxidation state of the atoms involved) because the magnitude of charge on each ion is eventually crisscrossed and gives the subscript (number of atoms) for each atom in the formula.
For instance, let us write the formula of calcium bromide. Ca has a charge of +2 while Br has a charge of -1. If we exchange the charges and ignore the signs such that the crisscrossed charges form subscripts we can now write;
.
Answer:
Because: The mixtures contain unwanted substances which may be harmful and may degrade the properties of mixtures. So we, need to separated them and extract useful substances.
Crayfish are very intolerant of pollution and other human-generated fouling of their environment. ... This abundance may be due more to the acid-generated absence of fish which prey on crayfish than to a direct, positive influence of the acid on the crayfish itself.