Question

criss cross method for formale of Na2HCO3​

Answer 1

Explanation:

To use this method, the absolute value of the oxidation number of the first ion is used as the subscript of the second, and vice versa. The subscripts are then reduced by the greatest common factor. For instance, to find the formula for aluminium oxide: The oxidation number of Al is +3 and oxygen is -2.

Answer 2

Explanation:

• Valency of Na is 1+
• Valency of HCO3 is 2-

Na HCO3

1+ 2-

Na2HCO3