Atomic Structure

Question 1

Elements

Answer 1

substances made up of only one type of atom

Question 2

three subatomic particles

Answer 2

Proons (+ charge)
Neutrons (neutral charge)
Electrons (- charge)

Question 3

The Role of protons, neutrons & electrons

Answer 3

-What determines the type of atom?
The number of protons
-What determines the mass of an atom?
The number of protons & neutrons
-What determines the net charge of an atom?
The ratio of protons to electrons
-What determines the stability of an atom?
The ratio of neutrons to protons

Question 4

Proton

Answer 4

Location: Nucleus
Mass: 1
Charge: +1
Role: Determines the identity of atom

Question 5

Neutron

Answer 5

Location: Nucleus
Mass: 1
Charge: 0
Role: Required for stability of nucleus

Question 6

Electron

Answer 6

Location: Orbit the nucleus
Mass: Negligible (0.0005)
Charge: -1
Role: Responsible for reactivity

Question 7

isotopes

Answer 7

atoms of the same element (same number of protons) that have a different number of neutrons.
E.g. the element Carbon has 3 known isotopes:
Carbon-12: 6 protons + 6 neutrons
Carbon-13: 6 protons + 7 neutrons
Carbon-14: 6 protons + 8 neutrons
The mass number on the periodic table is a calculated average of all known isotopes of an element, that’s why it is not a whole number. The equation accounts for the relative abundance of each isotope.

Question 8

ions

Answer 8

A neutral atom will have an equal number of protons and electrons. (overall charge = 0)
If the number of protons and electrons are not equal, the atom is now called an ion.
Positive ions are called cations.
Negative ions are called anions.