Mass number is the total number of Protons and Neutrons. Simply subtract 85 from 210. 210-85=125 neutrons
Answer:
18 is a
19 is c
20 i am not sure
Explanation:
18)nucleus contains protons and neutrons
Nonpolar covalent bonds are a type of chemical bond where 2 atoms share electrons with each other.
Polar covalent bonds are the same as nonpolar covalent bonds, but a pair of electrons are unequally shared between 2 atoms.
Ionic bonds are a type of linkage formed from the electrostatic attraction between oppositely charged ions in a chemical compound.
Hope this helps! ^-^
