SCIENCE 8th grade TEST: STRUCTURE OF MATTER

pure substance

A substance with a definite composition and set of chemical and physical properties.

Subscript

A number in a chemical formula that tells the number of atoms of each element that are in the molecule

Coefficient

A number in front of a chemical formula in an equation that indicates how many molecules are involved

Matter

Anything that has mass and takes up space (volume)

Atom

The smallest particle of an element and the basic unit of matter (it is made up of the subatomic particles protons, electrons, and neutrons)

Names and formulas reveal __________

chemical composition

Amorphous

describes solids with no pattern or order

Neutrons

has no charge, located in the nucleus of the atom

Nucleus has majority of the atom's ___________

mass

Electrons

negatively charged particles located in the electron cloud of the atom, moves at nearly the speed of light

Protons

positively charged particles, known as the atomic number, and determines the element

Molecule

smallest unit of a chemical compound, formed when two or atoms join together

Atomic mass

the average mass of all the protons and neutrons in a mass (the average atomic mass= Protons + neutrons amu)

Element

the basic form of matter which cannot be broken down any further, a pure substance made up of many atoms with the same atomic number

Compounds

two or more different atoms bonded together, the molecules of pure substances

The electron cloud has majority of the atom's __________

volume

Crystalline lattice

what causes crystals to form in their neat and order structure