BIOL 2030 Chapter2

Matter

anything that has mass and occupies space; solids, liquids, gases

Chemistry

study of matters and how different matters interacts

Law of Conservation of Matters

matter cannot be created or destroyed but it may change forms

Element

pure substance that can’t be broken down into other substances; 92; Oxygen, Carbon, Hydrogen, Silicon, Nitrogen etc…

Atom

smallest unit of an element that retain the chemicals properties of the element

Isotopes

atoms of a particular element that have differing numbers of neutrons

Radioisotope

isotope that sheds sub-atomic particles and emits radiation as it “decays”; not stable

Ion

atom that gains or loses electrons and therefore is no longer neutral

Molecules

two or more atoms bonded together

ex: O2, H2O

Compound

a molecule composed of atoms of two or more different atoms

ex: H2O

Bonding

attraction of atoms to one another’s elections holds them together

How many major plates moving a few inches per year?

Covalent bonds

electrons are shared between atoms

ex: H2O

Ionic bonds

electrons transferred from one atom to another, creating ions; atoms held together due to differing electrical charges

ex: NaCl

Polar Covalent bond

a covalent bond where electrons are shared unequally between atoms

Hydrogen bond

weak attraction between positions and negative parts of water molecules

pH

measure of H+ ion concentration

Organic compounds

contain Carbon (and other atoms) covalently bonded

ex: CH4, C2H6

Hydrocarbons

organic compounds with only C and H

Macromolecules

very large molecules found in living organisms

Proteins

polymers of amino acids

Carbonhydrates

polymers of simple sugar

Nucleic acids

polymers of nucleotides (sugar, phosphate, N base)

Lipids

have many structures, not necessary polymers

Polymers

long chains of repeated units

Energy

the capacity to accomplish work

Kinetic

energy due to motion

Potential

energy due to composition or position