8th Grade Science Crossword

Number of protons in the nucleus of an atom
A stable subatomic particle
A cloudlike group of electrons
A substance consisting of atoms which all have the same number of protons
The time required for a quantity to reduce to half its initial value
Any one of various forms in which the atoms of a chemical element can occur
The total number of protons and neutrons in a nucleus
A subatomic particle of about the same mass as a proton but without an electric charge
A very small particle of matter that is part of the nucleus of an atom and that has a positive electrical charge
A solid material that is typically hard, shiny, malleable, fusible, and ductile, with good electrical and thermal conductivity
An element or substance that is not a metal
A nonmetal that can combine with a metal to form an alloy
The smallest particle of a substance that can exist by itself or be combined with other atoms to form a molecule