Aneutral atom posseses an atomic number of 15 and an atomic mass or 31. three electrons are gained. what is the result of this conversion?

It becomes a P³⁻ ion.  

Step-by-step explanation:

Atom no. 15 is P.

If it gains three electrons, it becomes a phosphide ion, P³⁻.

the child will have heterozygous dominant chromosomes as characters of his father are dominant over the characters of his mother.

the child is heterozygous

out of these options:

ability to burn paper

pure sodium reacting violently with water

the boiling point of water

helium does not tend to react with anything

i would say this is a physical property:

helium does not tend to react with anything

why? :

i said helium does not tend to react with anything because well, it reacts to ! but ability to burn paper, pure sodium reacting violently with water, & the boiling point of water are chemical or

physical properties: the properties of a substance that can be observed without changing the chemical makeup of the substance

chemical properties: properties of a substance relating to the chemical nature and reactivity of the substance