| A | B |
|---|
| atom | basic unit of matter |
| nucleus | the centerof the atom wich contains the protons, and nutrons; in cells, structure that contains the cell's genetic material (DNA) and controls the cell's activity |
| electron | negitively charged partical;located outside the atomic nucleus |
| element | substance consisting entirely of one type of atom |
| isotope | atom of an element that has a number of nutrons differant from that of other atoms of the same element |
| compound | substance formed by the chemical combanation of two or more elements in definate proportions |
| ionic bond | bond formed when one or more electronsare transferred from one atom to another |
| ion | atom that has a positive or negitive charge |
| covailant bond | bond formed by the sharing of electrons between atoms |
| molecule | smallest unit of most most compounds |
| van der walls forces | a slight attraction that develops between the oppositely charged reigions of nearby molecules |
| cohesion | attraction between molecules of the same substance |
| adhesion | attraction between molecules of differant substances; in plants, attraction between unlike molecules |
| mixture | material composed of two or more elements or compounds that are physicallymixed together but not chemically combined |
| solution | mixture of two or more substances in wich the molecules of the substance |
