Studied by 12 peopleCarbon, Hydrogen, Nitrogen, Oxygen, Phosphorus, Sulfur
The most common elements found in living organisms.
subatomic particles
Protons, Neutrons, Electrons
Isotope
Different forms of the same element that have different numbers of neutrons.
Ion
A charged atom that has gained or lost electrons.
Mass Number
The sum of the number of protons and neutrons in an atom.
Atomic Number
The number of protons in the nucleus of an atom.
Electronegativity
The tendency of an atom to attract electrons.
Noble Gases
The elements in the rightmost column of the periodic table that have a full outer shell of electrons and do not react with other elements.
Valence Electrons
Electrons in the outermost shell of an atom.
Ionic Bond
A bond formed when one atom donates an electron to another atom.
Covalent Bond
A bond formed when two atoms share electrons.
Polarity
Uneven distribution of electrons among atoms connected by a chemical bond.
Polar Molecule
A molecule with partially positive and partially negative charges.
Nonpolar Molecule
A molecule with an even distribution of electrons and no partial charges.
Hydrogen Bond
Weak attraction between water molecules due to the partial positive and partial negative charges.
Molecule
Two or more atoms held together by chemical bonds.
Compound
A substance made up of two or more atoms of different elements.
Chemical Change
A reaction that forms new products
Physical change
Matter changes form but not chemical identity
pH
Power of Hydrogen; a measure of hydrogen ion concentration.
Acids
Increase the hydrogen ion concentration of a water solution
Bases
Decrease the hydrogen ion concentration of a water solution.
pH Scale
Ranges from 0-14. Any pH value above 7 is a Base, any pH value below 7 is an acid.
Buffers
Any compound(s) that can both increase or decrease hydrogen ion concentration to maintain homeostasis.
Carbonic Acid
Bicarbonate Buffer System
Properties of water
Universal Solvent, Cohesion, Adhesion, High Specific Heat, High Heat of Vaporization, Density Changes
Dissociate
Compound breaks into ions in a solution
Cohesion
Water is attracted to other water molecules due to hydrogen bonding. Causes high surface tension.
Adhesion
Water is attracted to other substances that are polar/charged.
Capillary action
Water sticks to the walls of plant cell capillaries and travels up the plants
High specific heat
Water temperature changes slowly and holds temperature well.
High heat of vaporization
Water requires a lot of energy to change state.
Density Changes
Ice floats - solid water molecules form a lattice that is less dense than liquid water and therefore floats.
