Chapter 2: Atomic Structure

Question 1

What are atoms?

Answer 1

They are small particles from which all the material world is built. In other words, it is the basic building block of all matter

Question 2

What are elements?

Answer 2

They are one type of atom that cannot be broken down into simpler things. In other words, they are the same type of atoms chemically combined.

Question 3

What is a compound?

Answer 3

It is two or more than one type of atom chemically combined.

Question 4

How many subatomic particles does an atom have?

Answer 4

Three

Question 5

What are the subatomic particles of an atom?

Answer 5

Proton, neutron, and electron

Question 6

What is the charge of a proton?

Answer 6

They have a positive charge

Question 7

What is the charge of a neutron?

Answer 7

They have a neutral charge(no charge)

Question 8

What is the charge of an electron?

Answer 8

They have a negative charge

Question 9

What subatomic particles are found in the nucleus of an atom?

Answer 9

Protons and neutrons

Question 10

What is the relative mass of protons and neutrons?

Answer 10

1 amu

Question 11

What is the relative mass of an electron?

Answer 11

Negligible(1/1840 amu)

Question 12

What are neutrons responsible for?

Answer 12

They are responsible for the stability of the atom because they increase the space between the protons and electrons.

Question 13

What is the mass number?

Answer 13

It is the number of protons plus neutrons in an element

Question 14

What does an atomic number tell us?

Answer 14

It tells us the number of protons in an element

Question 15

What are isotopes?

Answer 15

They are atoms of the same element with the same number of protons and electrons but different numbers of neutrons. They have the same chemical properties and electronic configuration. However, their physical properties might differ.

Question 16

Calculat the average atomic mass of oxygen if its abundance in nature is:
99.76% 16O
0.04%17O
0.20%18O

Answer 16

16 amu

Question 17

How many electrons can the first shell hold?

Answer 17

2

Question 18

How many electrons can the second and third shell hold?

Answer 18

8

Question 19

What do electrons orbit?

Answer 19

The central nucleus of the atom

Question 20

True or false? Shells that are closer to the nucleus have higher energy:

Answer 20

False

Question 21

What will the number of shells show us?

Answer 21

The period that element is in

Question 22

What will the number of outer electrons show us

Answer 22

The group that element is in

Question 23

Complete the statement: Elements in the same group have the same…

Answer 23

Number of outer shell electrons

Question 24

Complete the statement: Elements in the same period have the same…

Answer 24

Number of shells

Question 25

What's the electronic configuration of argon?(It has 18 electrons)

Answer 25

2,8,8

Question 26

What's the electronic configuration of sodium?(It has 11electrons)

Answer 26

2,8,1

Question 27

What are noble gases?

Answer 27

They are the atoms of group 8, and they all have 8 valence electrons(except for helium).

Question 28

Are noble gases reactive? Why or why not?

Answer 28

No, because they are stable since they have a full outer shell, so they don't wish to fill their outer shell with electrons.