Atomic Structure

xiaole's version from 2018-03-03 15:17


Question Answer
What are Isotopes?they are atoms from the same element but contain different number of neutrons
What is the valence shell?it is the outermost shell of an atom
what is a nucleus?it contains the protons and neutrons of an atom
Describe a Valence electronan electron in the outermost shell
What is an atomic number?the number of protons in the nucleus of the atom
Define the mass numberthe total number of protons and neutrons in a nucleus.
what is an ion?An ion is a particle that has electrical charge. The charge is either positive or negative
Define cationa positively charged Ion
Define aniona negatively charged ion
describe a polyatomic ionA polyatomic ion is a molecule that has electrical charge, either positive or negative.
What is an ionic bond?It is a bond between oppositely charged ions (usually a nonmetal and metal)
What is covalent bond?A bond between atoms that share electrons (usually non metal)
Define molecule A molecule is a single particle that is composed of two (or more) nonmetal atoms that are held together by covalent bond(s)
What is a formula unit?The lowest whole number ratio of the ions in an ionic compound. A formula unit of an ionic compound is used analogously to molecule of a molecular compound.
What is molecular mass?The sum of atomic masses of all atoms in a molecule.
define a moleIt is a unit that measures the amount of particles in a substance (6.022 x 1023)
Define Molar massThe mass in grams that is numerically equal to the atomic mass of the element.
What is the empirical formula?Gives the smallest whole number ratio of the elements in a compound
What is molecular formula?Gives the actual whole number ratio of elements in the compound.