Question

based on the model shown, what is the formula for a compound containing only li and o?
a lio
b lio₂
c li₂o₂

Explanation:

Step1: Determine the valency of Li and O

Lithium (Li) has a valency of +1 as it can lose one electron to achieve a stable electron - configuration. Oxygen (O) has a valency of -2 as it needs to gain two electrons to achieve a stable electron - configuration.

Step2: Use criss - cross method to find the formula

To form a neutral compound, we use the criss - cross method. The valency of Li becomes the subscript of O and the valency of O becomes the subscript of Li. So the formula is $Li_2O$.

Answer:

C. $Li_2O$