 | Term | Definition |
| |
atom |
basic unit of matter |
| |
nucleus |
center of an atom, contains protons and neutrons |
| |
electron |
negatively charged subatomic particle located outside the nucleus. |
| |
element |
a form of matter that contains only one kind of atom |
| |
isotope |
atoms of the same element with different numbers of neutrons in their nuclei. |
| |
compound |
substance formed by the chemical combination of two or more elements in definite proportions |
| |
ionic bond |
formed when one or more electrons are transferred from one atom to another |
| |
ion |
positively or negatively charged atom |
| |
covalent bond |
bond whose electrons are shared between atoms |
| |
molecule |
the smallest unit of most compounds |
| |
van der Waals forces |
a slight attraction that develops between the oppositely charged regions of nearby molecules |
| |
cohesion |
an attraction between molecules of the same substance |
| |
adhesion |
attraction between molecules of different substances |
| |
mixture |
a material composed of two or more elements or compounds that are physically mixed together but not chemically combined |
| |
solution |
mixture where all components are evenly distributed |
| |
solvent |
substance in which a solute is dissolved to form a solution |
| |
solute |
substance that is dissolved in a solvent to make a solution |
| |
suspension |
mixture of water and nondissolved materials |
| |
pH scale |
measurement system used to indicate the concentration of hydrogen ions in solution: ranges from 0-14 |
| |
acid |
compound that forms hydrogen ions in solution |
| |
base |
compund that produces hydroxide ions in solutions |
| |
buffer |
weak acids or bases that can react with strong acids or bases to prevent sharp sudden changes in pH |
| |
monomer |
small unit that can join together with other small units to form polymers |
| |
polymer |
large compound formed from combinations of many monomers |
| |
carbohydrate |
key source of energy; organic compunds made of carbon, hydrogen, oxygen. |
| |
monosaccharide |
single sugar molecule (monomer) |
| |
polysaccharide |
large macromolecule formed from monosaccharides |
| |
lipid |
macromolecules made of carbon and hydrogen, fats, oils, and waxes |
| |
nucleic acid |
macromolecule containing carbon, hydrogen, oxygen, nitrogen, and phosphorus |
| |
nucleotide |
monomer of a nucleic acid made of a five-carbon sugar, a phosphate group, and a nitrogenous base |
| |
ribonucleic acid |
(RNA) single-stranded nucleic acid that contains the sugar ribose |
| |
deoxyribonucleic acid |
(DNA) nucleic acid that contains the sugar deoxyribose |
| |
protein |
macromolecule that contains carbon, hydrogen, oxygen, and nitrogen; needed by the body for growth and repair, and to make enzymes |
| |
amino acid |
basic building block for protein compound with an amino group (−NH2) on one end and a carboxyl group (−COOH) on the other end |
| |
chemical reaction |
a process that changes one set of chemicals into another set of chemicals |
| |
reactant |
the elements or compounds that enter into a chemical reaction |
| |
product |
the elements or compounds that are produced by a chemical reaction |
| |
activation energy |
the energy that is needed to get a reaction started |
| |
catalyst |
a substance that speeds up the rate of a chemical reaction |
| |
enzyme |
proteins that act as a cell's biological catalysts |
| |
substrate |
The reactants of an enzyme catalyzed reaction |
