Chem Unit 3 vocab

Atom

Atom

smallest partical of an element that still retains the properties of that element

proton

positively charged subatomic particle located in the nucleus

Neutron

neutral charged partical

electron

negatively charged particle located in electron cloud.

atomic number

determines the identity of the element on the periodic table

mass number

a count of the number of the protons and neutrons located in the nucleus

period

horizontal row on the periodic table that refers to how many energy levels an atom has

valence electrons

electrons in the outer most energy level

Bohr models

a model to show the possible location of electrons in the electron cloud.

electron dot diagram

uses the symbol of the element and dots to represent its valence electrons

groups

vertical columns on the periodic table

alkali metals

Group 1 (1A) elements

Alkaline earth metals

Group 2 (2A) elements

Halogens

Group 17 (7A) elements (means “Salt-former)

Noble gases

group 18 (8A) elements inert gases that do not undergo chemical reactions

transitional metals

elements in groups 3-12

metals

good conductors, have luster, and are malleable and ductile

non-metals

elements that are dull, poor conductors, and are gases or brittle solids at room temp

semiconductor

element that conducts electricity under certain conditions.