What must the charge of X be if it is written correctly
as XN?
O
+3
+1
O
-1

+3

Explanation:

Let's consider the chemical formula XN. It must be formed by a cation coming from X and an anion coming from N. Nitrogen has only one negative charge: -3. We know, that the sum of the charges of the elements that form a compound is equal to the charge of the compound. considering XN is a neutral compound (charge 0), we can use this information to calculate the charge of X.

X + N = 0

X + (-3) = 0

X = +3

o conteúdo de calor de um sistema é igual à entalpia apenas para um sistema que é constante