Question

please
help fast I will mark you the breinliest​

Answer 1

Answer:

X(HCO3)2

X(NO2)2

Explanation:

valency of X is 2

Answer 2

Explanation:

The formula is xso4, so the valancy of x must be +2

So by using this we can write its bicorbonate as

X(HCo3)2

And its nitrate as

X(No3) 2