A phosphorus atom needs to gain ---electrons to achieve a full octet

Three (3).

Explanation:

The octet rule is a rule in chemistry that states that, chemical elements would either gain or loss electrons in their outermost shell in order to attain a stable electronic configuration i.e having eight (8) valence electrons in their outermost shell such as chemical elements found in group 8 (2-8-8) known as noble gas.

A phosphorus atom needs to gain three (3) electrons to achieve a full octet because the atomic number of phosphorus is 15 and as such it has the electronic configuration of 2-8-5 and needs three electron in order to become a stable element.

answer: the exterior temperature of commercial jet planes as they leave the stratosphere and return to the ground increases steadily.

explanation:

the lower most layer of atmosphere is troposphere which extends from 0 to 12 km above the surface of the earth. the temperature initially decreases as distance is increased from the earth's surface. commercial jets fly in lower part of the stratosphere. the stratosphere extends upto 50 km. the temperature in stratosphere starts rising again due to presence of ozone which traps the uv rays.

thus, when the planes leave the stratosphere and return to the ground, the exterior temperature increases steadily.

i just did an experiment like this in my science class. also the answer is yes, it will get separated because they are two opposites meaning if they are opposite they can not attract.

hope this .!