How many electrons does a phosphorus atom need to achieve a noble gas configuration

Explanation:

In order to have a full shell it needs eight. It is easier to gain three electrons instead of losing five. Therefore phosphorus tends towards P3−

if the concentration of products is decreased, the equilibrium will shift toward the products). add an inert gas (one that is not involved in the reaction) to the constant-volume reaction mixture: this will increase the total pressure of the system, but will have no effect on the equilibrium condition.

explanation:

we can conclude that the melting point of table salt is above room temperature (it's actually 801 deg c). the melting point of mercury must be below room temperature (- 39 deg c).