Atomic Structure

Question 1

Define atomic number.

Answer 1

The number of protons in an atom.

Question 2

Define atomic mass.

Answer 2

The number of protons and neutrons in an atom.

Question 3

Define isotope.

Answer 3

Atoms of the same element that have the same number of protons but a different number of neutrons.

Question 4

Mass is expressed as a.m.u. What does this stand for?

Answer 4

Atomic mass unit.

Question 5

Why are models used to represent atoms?

Answer 5

To help understand atomic properties and behaviour.

Question 6

What is the atomic charge of a proton?

Answer 6

+1

Question 7

What is the atomic charge of a neutron?

Answer 7

0

Question 8

What is the atomic charge of an electron?

Answer 8

-1

Question 9

What is the atomic mass of a proton?

Answer 9

1

Question 10

What is the atomic mass of a neutron?

Answer 10

1

Question 11

What is the atomic mass of an electron?

Answer 11

1/2000 (0.0005)

Question 12

Electrons rotate at extreme velocities. What does this create?

Answer 12

A cloud, which is known as an orbital.

Question 13

What defines the chemical identity of an element?

Answer 13

The number of protons.

Question 14

If an atom were to gain or lose a proton, what would happen to the atom?

Answer 14

It would transmutate into a different atom.

Question 15

Why does transmutation not occur?

Answer 15

Protons are held together by a strong nuclear force and a lot of energy would be needed to overcome this force.

Question 16

In a diagram, what symbol represents atomic number?

Answer 16

A

Question 17

In a diagram, what symbol represents atomic mass?

Answer 17

Z

Question 18

How do you calculate the number of neutrons an atom possesses?

Answer 18

Atomic mass (Z) - Atomic number (A)

Question 19

How do you calculate the number of protons an atom possesses?

Answer 19

Atomic number (A).

Question 20

How do you calculate the number of electrons an atom possesses?

Answer 20

Atomic number (A).

Question 21

What are the two other isotopes of Hydrogen?

Answer 21

1. Deuterium.

2. Tritium.

Question 22

What are the three important features of Hydrogen’s isotopes?

Answer 22

1. They are the entry-port for neutrons.
2. There would not be any other chemical element as Helium and other heavier elements could not form.
3. They are the fuel for our Sun; there would be no life on Earth if photosynthesis wasn’t possible.