atom vocab

Question 1

atom

Answer 1

An atom is the smallest particle of an element that still has all the properties of the element.

Question 2

atomic number

Answer 2

the number of protons in the nucleus of an atom.

Question 3

electron

Answer 3

a negatively charged particle that moves around the nucleus

Question 4

electron dot diagram

Answer 4

a diagram that shows the element symbol surrounded by dots
representing valence electrons.

Question 5

element

Answer 5

a pure substance that cannot be broken down into simpler substances by
ordinary chemical means

Question 6

energy level

Answer 6

a particular region where electrons can orbit a nucleus.

Question 7

ion

Answer 7

an atom or molecule that has an electrical charge because it has gained or lost
electrons

Question 8

isotope

Answer 8

one of several forms of the same element

Question 9

mass number

Answer 9

the number of protons plus neutrons in the nucleus of an atom.

Question 10

neutron

Answer 10

a particle with no charge located in the nucleus of an atom.

Question 11

nucleus

Answer 11

the positively charged, dense center of an atom.

Question 12

periodic table

Answer 12

a chart that organizes the chemical elements based on their properties.

Question 13

proton

Answer 13

a positively charged particle located in the nucleus of an atom.

Question 14

radioactive

Answer 14

capable of releasing radiation.

Question 15

valence electrons

Answer 15

electrons found in the outermost energy level of an atom