Question #18660

2 Answers
May 1, 2017

Answer:

Phosphorus can have both a positive and a negative valency.

Explanation:

If phosphorus combines with a metallic element it has a negative valance. The phosphorus because it has a higher electron negativity than the metals will act as an oxidizer taking electron away from the positive metals. This creates a valance of -3

If phosphorus combines with a non metal element with a higher electron negativity than phosphorus it will have a positive valance.

When phosphorus combines with Oxygen to form an phosphate ion it has a charge of +5 # PO_3^-1# This is because Oxygen will act as the oxidizer taking the electrons away from the phosphorus.

Phosphorus can have either a positive valance or a negative valance depending on what other element it is combining with and the relative electron negativity of the other elements.

Jul 15, 2017

Answer:

Phosphorus has neither a positive or negative valency.

Explanation:

Valency is the number of #"H"# atoms or #"Cl"# atoms that can form bonds to a particular element.

Thus, in #"PH"_3# and in #"PCl"_3# the valency of phosphorus is 3.

In #"PCl"_5# the valency of phosphorus is 5.