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 found in the nucleus of an atom.

Question 6

Neutron

Answer 6

a particle of matter that has no electrical charge and found in 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

= the number of protons in an element’s atoms. 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

Subscript

Answer 10

Tiny number to the right of the element symbol. Tells you how many atoms of that element.

Question 11

Chemical symbol

Answer 11

A one or two letter representation of an element.