1.1 The Fundamental Chemistry of Life

Atomic Structure

- atomic number= number of protons
- mass number= protons + neutrons
- the bottom number is the atomic number

Isotopes are different forms of the same element with different atomic masses (different number of neutrons)

Radioisotopes is a radioactive isotope of an element

Chemical Bonds

Ionic bonds are formed between atoms that
have gained/lost electrons to become charged
- positive ion = cation
- negative ion = anion

Covalent Bonds form when atoms share one or more pairs of valence electrons.
- Electronegativity is the measure of an atom's attraction for additional electrons. It will increase as the distance between the electrons & the nucleus decrease

Polar Covalent Bond is the unequal sharing of electrons between 2 atoms with different electronegativity.

Intermolecular forces is the force or attraction between
2 molecules
- a.k.a van der Walls forces are very weak attractions between 2 molecules or parts of molecules, when they are close together

Hydrogen bonds are the attractive force
2 partially positively charged hydrogen atom
& a partially negatively charged atom in another
molecule. They are the strongest bonds VDW
force but individual bonds are weak compared to
ionic and covalent bonds

Chemical Reactions-there
are 4 major types of chemical
reactions in biological processes

Dehydration Reactions (condensation) is when OH & H are removed from 2 reactants then form together to make a H2O and the reactants form together. They are mostly used to create larger molecules like carbs and proteins

Hydrolysis reactions is the opposite of dehydration where water is used as a reactant to split a large molecule

Neutralization reactions is when an acid + base= salt and water.

Redox reactions is when electrons are lost from one atom and gained by another.
- oxidation= when a molecule lost electrons
- reduction= when a molecule gains electrons

Electron Arrangements

Orbitals are a region of space
that has electrons that are around
the nucleus

Valence electrons are the electrons in
the outermost energy shell