AP Chem Ch 2

Acids

proton donors

alkali metals

any metal in Group 1A of the periodic table

alkaline earth metals

the elements in Group 2A of the periodic table

Allotropes

two or more different molecular forms of the same element in the same physical state

alpha particle

a type of nuclear radiation consisting of two protons and two neutrons

Anion

A negatively charged ion

Atom

Smallest particle of an element

atomic number

the number of protons in the nucleus of an atom

Base

a compound that produces hydroxide ions in solution

beta particle

A fast-moving electron that is given off as nuclear radiation

binary compound

a compound composed of two elements

Cation

A positively charged ion

diatomic molecule

A molecule consisting of two atoms

empirical formula

a formula with the lowest whole-number ratio of elements in a compound

hydrate

A compound that has a specific number of water molecules bound to its atoms

Isotope

Atoms of the same element that have different numbers of neutrons

Law of Conservation of Mass

Matter is not created nor destroyed in any chemical or physical change

law of definite proportions

a given compound always contains exactly the same proportion of elements by mass

Law of Multiple Proportions

elements can combine in different ratios to form different compounds

Oxoacids

acids that contain hydrogen, oxygen, and another element

Oxoanions

polyatomic ions that contain oxygen in combination with one or more other elements

structural formula

a formula that shows the arrangement of atoms in the molecule of a compound.

ternary compound

a compound composed of three different elements