Honors Chemistry: Chapter 3 (excluding section 3)
|chemical reaction||the transformation of a substance or substances into one or more new substances|
|law of conservation of mass||states that mass is neither created nor destroyed during ordinary chemical reactions or physical changes|
|law of definite proportions||fact that a chemical compound contains the same elements in exactly the same proportions by mass regardless of the size of the sample or source of the compound|
|law of multiple proportions||if two or more different compounds are composed of the same two elements, then the ratio of the masses of the second element combined with a certain mass of the first element is always a ratio of small whole numbers|
|Atomic Theory||1. All matter is composed of extremely small particles called atoms.|
2. Atoms of a given element are identical in size, mass, and other properties.
3. Atoms cannot be subdivided, created, or destroyed.
4. Atoms of different elements combine in simple whole-number ratios to form chemical compounds.
5. In chemical reactions, atoms are combined, separated, or rearranged.
|atom||the smallest particle of an element that retains the chemical properties of that element|
|nucleus||a very small particle of an element that retains the chemical properties of that element|
|proton||a positively charged particle|
|electrons||negatively charged particles that surround the nucleus|
|subatomic particles||protons, neutrons, and electrons|
|alpha particles||positively charged particles with about four times the mass of a hydrogen atom|
|nuclear forces||short-range proton-neutron, proton-proton, and neutron-neutron forces hold the nuclear particles together|