Matter Matters
Pure substances include elements and ________.
compounds
The center of an atom is called the ________.
nucleus
Elements in the same column of the periodic table are called ________.
Groups or Families
Ionic bonds are formed when electrons are ________.
transferred
The starting substances in a chemical reaction are called ________.
Reactants
This type of mixture has a uniform composition throughout.
homogeneous
Electrons orbit the nucleus in specific paths called ________.
energy levels or shells
The atomic number represents the number of ________ in an atom.
Protons
A bond in which atoms share electrons is called ________.
covalent bond
This type of reaction involves the combination of two substances into one.
synthesis
A solution where particles settle over time is called a _____________
suspension or precipitate
This subatomic particle has no charge.
Neutrons
Elements in Group 18 are known as ________.
Noble Gases
Metallic bonds form a “sea of ________.”
electrons
The Law of Conservation of Mass states that mass cannot be ________ or ________.
Created or Destroyed
This phase change occurs when a liquid turns into a gas
vaporization
The mass number is the sum of an atom’s ________ and ________.
The reactivity of elements is largely determined by their ________.
Valence Electrons
The bond between sodium (Na) and chlorine (Cl) in NaCl is ________.
Ionic
A reaction where energy is absorbed is called ________.
Endothermic
Colloids differ from solutions because their particles are ________ but do not settle
Larger
Atoms of the same element with different numbers of neutrons are called ________.
Isotopes
This element is the most abundant metal in the Earth’s crust.
Aluminium
Carbon atoms often form this type of covalent bond involving multiple shared electrons.
Double or triple bond
When balancing equations, you adjust these numbers in front of compounds.
coefficients