Question

Match the elements with their valencies.

• A. 3
• B. 2
• C. 0
• D. 1

Answer 1

$\bullet$ The valency of an element is a measure of its combining power with other atoms when it forms chemical compounds or molecules.

$\bullet$ The valency of an element is related to the number of electrons present in the outer shell.
The valency of different groups can be summed up as in the below given table:
Looking at the table, we can say, valency of hydrogen, magnesium, phosphorus and krypton is 1, 2, 3 and 0 respectively.