chemistry review for bio


A positively charged ion


A negatively charged ion

why are ions important?

conduct electrical currents, muscles and nerves work bc of them, electrolytes


atoms with different number of neutrons but same amount of protons and electrons

the number on the top left of an isotopic symbol is the

atomic mads

the number on the BOTTOM left of an isotopic symbol is the

number of protons/electrons

why are isotopes important for the human body?

using nuclear medicine, radioactive ones will show images of organs/body parts to diagnose/detect problems and also treat diseases


made of more than one type of atom


made of more than one of the SAME atom

chemical reactions

making and breaking of bonds, forming new substances

ionic bonds

ions form electrons are lost or gained, then attract to each other to form a bond (ex. sodium chloride)

covalent bond

strongest bond, share electrons with an atom (ex. water)

nonpolar covalent

atoms shares electrons ewually

polar covalent

atoms share electrons unequally, making one part positive and the other part of the molecule negative

hydrogen bonds

the positive hydrogen of one molecule is attracted to a negative part of another polar molecule (ex. As-Ts , Cs-Gs)

van der waals forces

very short-lived, quick attracting between molecules holding them together, very weak (ex. geckos walking on walls)