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Chemistry/ CH. 4
Atoms
Word | Definition |
---|---|
Atom | The smallest particle of an element that retains its identity in a chemical reaction. |
Atomic Mass | The weighted average mass of the atoms in a natural occurring sample of an element. |
Atomic Mass Unit (AMU) | One twelve of a carbon-12 atom. |
Atomic Number | The number of protons in the nucleus of an atom of that element. |
Cathode Ray | A glowing beam that traveled from the Cathode disk to the Anode disk. |
Electrons | Negatively charged subatomic particles. |
Group | The vertical columns of the periodic table. |
Isotopes | Atoms that have the same number of protons but different number of neutrons. |
Mass Number | The total number of protons and neutrons in an atom. |
Neutron | Subatomic particles with no charge but with a mass nearly equal of that of a proton. |
Nucleus | The tiny central core of an atom and is composed of protons and neutrons. |
Period | The horizantal rows of the periodic table. |
Periodic Table | An arrangement of elements in which the elements are seperated into groups based on a set of repeating properties. |
Proton | Positively charged subatomic particals. |
Daltons Atomic Theory 1 | 1. All elements are composed of tiny invisible particles called atoms. |
Daltons Atomic Theory 2 | 2. Atoms of the same element are identicle. The atoms of any one element are different from those of any other element. |
Daltons Atomic Theory 3 | 3. Atoms of different elements can phisically mix together or can chemically combine in simple whole-number ratios to form compounds. |
Daltons Atomic Theory 4 | 4. Chemical reactions occur when atoms are seperated, joined, or rearranged. Atoms of one element, however never changed into atoms of another element as a result of chemical reaction. |