Two chromate ions are contained in this compound. The “di” prefix means Two
Mono- one
Di- two
Tri- three
Tetra- four
Penta- five
Hexa-six
Hepta- seven
Octa- eight
Nona- nine
Deca- ten
Answer:

Explanation:
From the given information, since the molecular mass of the ion M+ is not given;
Let's assume M+ = 58.0423
So, by applying the 13th rule;
we will need to divide the mass by 13, after dividing it;
The quotient n = no. of carbon; &
The addition of the quotient (n) with the remainder r = no. of hydrogen.
So;

So;


From the given information; we have oxygen present, so since the mass of oxygen = 16, we put oxygen in the molecular formula by removing
. Also, since the mass is an even number then Nitrogen is 0.
So, we have:

Metals are the type of elements that are most likely to form more than one type of ion, for instance iron can form the ion of Fe^2+ or Fe^3+.