Question

write the chemical formula of an oxide of metal X having valency 3​

Answer 1

Explanation:

Electronic configuration of a element which can have valency 3

Atomic Number 13 - Aluminum

Oxide of Aluminum = Al2O3

Answer 2

Using criss - cross method of finding chemical formula

valancy of x=+3

valancy of o=-2

X * O

+3 * -2

After cross over valencies , formula will be X2O3.

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