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 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 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.