1.1 Subatomic Particles

Question 1

Protons

Answer 1

• protons are found in the nucleus of an atom
• each proton has an amount of charge equal to the fundamental unit of change (e=1.6x10^-19 C) we denote this fundamental unit of change as “+1e “ or “+1” for the proton
• protons have a mass of approx. one atomic mass unit (amu)

Question 2

Atomic Number Z

Answer 2

• is equal to the number of protons found in an atom of that element
• elements are defined by the number of protons they contain (ex: all atoms of oxygen contain 8 protons)
• while all atom of an element have the same atomic number they do not necessarily have the same mass

Question 3

Neutrons

Answer 3

• are neutral, they have no charge
• a neutrons mass is only slightly larger than that of the proton, and together, the protons and the neutrons of the nucleus make up almost the entire mass of an atom

Question 4

Mass Number (A)

Answer 4

• every atom has a characteristic of mass number (A), which is the sum of the protons and neutrons in the atoms nucleus

Question 5

Isotopes

Answer 5

Atoms that share an atomic number but have different mass numbers are known as isotopes of the element

Question 6

The convention A/Z X

Answer 6

Is used to show both the atomic number (Z) and the mass number (A) of atom X

Question 7

Electrons

Answer 7

• Move through the space surrounding the nucleus and are associated with varying levels of energy
• Each electron has a charge equal in magnitude to that of a proton, but with the opposite (negative) sign, denoted by “-1e” or simply “-1”
• The mass of an electron is approx. 1/2000 that of a proton

Question 8

Valence Electrons

Answer 8

• Electrons closer to the nucleus are at lower energy levels, electrons far from the nucleus have strong interaction with the surrounding environment and the weakest interactions with the nucleus
• they are much more likely to become involved in bonds with other atoms because they experience the least electrostatic pull from their own nucleus
• determine the reactivity of an atom

Question 9

Cation

Answer 9

A positively charged atom

Question 10

Anion

Answer 10

A negatively charged atom

Question 11

The sharing or transferring of valence electrons in bonds allows elements to

Answer 11

Fill their highest energy level to increase stability

• in the neutral state, they’re equal numbers of protons and electrons, losing electrons results in the atom gaining a positive charge, well gaining electrons results in the atom gaining a negative charge