Unit 1: Biochemistry

Vocab:

Matter = Anything that takes up space and has mass.

Element = Substance that cannot be broken down into other substances by chemical reactions.

Essential element = Elements required for an organism to live and reproduce. Hydrogen, oxygen, carbon, nitrogen are the main essential elements. There are also some trace elements.

Compound = substance consisting of 2 or more different elements.

Molecule = substance consisting of 2 or more elements. Not necessarily different.

Atom diagram

Atom = Smallest unit of matter. Still retains the properties of an element.

Subatomic particles = two nuclear subatomic particles: Proton (+tive charge) and neutrons (no charge); and 1 orbiting subatomic particle: Electron (-tive charge).

atomic number= number of protons.

atomic mass= Average weight of number of protons plus neutrons.

isotope= Different atomic forms of the same element (different number of neutrons).

Valance shell= outer shell of electrons. Bonding part of an atom. Either 2 (first) or 8 (all others) electrons.

Chemical bond= sharing or taking of electrons.

covalent bond= sharing a pair of two valence electrons by two atoms. It is the strongest bond.

Ionic bond= Atom taking an electron from another atom. Forms between a cation and a anion. Weak bond in aqueous solutions.

Electronegativity = The power of an atom to attract electrons to itself.

Non polar bond= Electrons are shared equally.

Polar bond= Electrons are not shared equally.

Anion= negative ion.

Cation= positive ion.

Hydrogen bond= Bond between hydrogen and an electronegative atom. See high specific heat.

Acid= Substance that increases the hydrogen ion concentration of a solution.

Base= Substance that reduces the hydrogen ion concentration of a solution.

Molecular mass= the molecular mass of a molecule is equal to the sum of the atomic masses of it's elements.

Avogadro's number= 6.02*10^23

Molar mass= a molecule's molar mass is equal to the molecule's molecular mass number in grams. This is called 1 mole. It is also equal in mass to an Avogadro's number amount of the molecule.

Organic chemistry = Study of compounds containing carbon.

Hydrocarbon= Molecule of only hydrogen and carbon.

Macromolecule= Very large molecule. These include carbohydrates, proteins, and nucleic acids.

Polymer= Long molecule consisting of many similar or identical building blocks linked by covalent bonds.

Monomer= The similar or identical building block used in a polymer.

Enzyme= Specialised macromolecules that speed up chemical reactions.