Topic 1: key concepts of chemistry

Question 1

what does (s) stand for?

Answer 1

solid

Question 2

what does (l) stand for?

Answer 2

liquid

Question 3

what does (g) stand for?

Answer 3

gas

Question 4

what does (aq) stand for?

Answer 4

aqueous

Question 5

what does the term (aq) mean?

Answer 5

dissolved in water

Question 6

balance this ionic equation

__Fe + __Cl2 —> __FeCl3

Answer 6

2Fe + 3Cl2 —> 2FeCl3

Question 7

How had Dalton’s theory changed over time?

Answer 7

they changed due to the discovery of subatomic particles

Question 8

describe the structure of an atom as a nucleus

Answer 8

An atom has a central nucleus surrounded by electrons arranged in areas called shells.

Question 9

what is the relative charge and mass of a proton

Answer 9

relative mass: 1, relative charge: +1

Question 10

what is the relative charge and mass of a neutron

Answer 10

relative mass: 1, relative charge: 0

Question 11

what is the relative charge and mass of a electron

Answer 11

relative mass: 1, relative mass: -1

Question 12

why do atoms contain equal numbers of protons and electrons?

Answer 12

protons and electrons have equal and opposite charges, so that atoms are neutral overall.

Question 13

Describe the nucleus of an atom compared to the

overall size of the atom

Answer 13

the diameter of a nucleus can be 100,000 times less than the diameter of an atom