Atoms, Elements, Molecules, and Compounds

Question 1

Atom

Answer 1

the smallest particle of an element that can exist

Question 2

Element

Answer 2

a pure chemical substance that cannot be physically split into a more simple substance. Each is made of one type of atom. Carbon, mercury and hydrogen are examples.

Question 3

Molecule

Answer 3

the smallest particle of a substance that can exist. It is composed of two or more atoms.

Question 4

Compound

Answer 4

a substance made of atoms from two or more elements.

Question 5

Proton

Answer 5

a particle of matter that has a positive electrical charge and forms part of the nucleus of an atom.

Question 6

Neutron

Answer 6

a particle of matter that has no electrical charge and forms part of the nucleus of an atom.

Question 7

Electron

Answer 7

a particle of matter that has a negative electrical charge and travels around the nucleus of an atom.

Question 8

Atomic Number

Answer 8

Number of protons. Top number in the element box.

Question 9

Mass Number

Answer 9

Number of protons plus neutrons. Bottom number in the element box.

Question 10

Chemical Symbol

Answer 10

a one or two letter representation of an element.

Question 11

Subscript

Answer 11

tiny number to the right of the element symbol. tells you how many atoms of that element.