Ch. 7 Vocab Flashcards
Average mass of an atom of an element; it’s unit of measure is the atomic mass unit (u) which is 1/12 the mass of a carbon-12 atom.
Atomic mass
Number of protons in the nucleus of each atom of a given element; is the top number in the periodic table.
Atomic number
A substance produced when elements combine and whose properties are different from each of the elements in it.
Compound
Negatively charged particle that exist in an electron cloud formation around an atoms nucleus.
Electron
Region surrounding the nucleus of an atom, where electrons are most likely to be found.
Electron cloud
Substance that cannot be broken down into simpler substances.
Element
Two or more atoms of the same element that have different numbers of neutrons in their nuclei.
Isotopes
Sum of the number of protons and neutrons in the nucleus of an atom.
Mass number
Element that is malleable, ductile, a good conductor of electricity, and generally has a shiny or metallic luster.
Metal
Element that share some properties with both metals and nonmetals.
Metalloid
A combination of compounds and elements that has not formed a new substance in whose proportions can be changed without changing the mixtures identity.
Mixture
Electrically neutral particle that has the same mass as a proton and is found in an atoms nucleus.
Neutron
Element that is usually a gas or brittle solid at room temperature it is a poor conductor of heat and electricity
Nonmetal
Positively charged particle in the nucleus of an atom.
Proton
Matter that has the same composition and properties throughout.
Substance
