2.1 Matter

Question 1

How many elements are there?

Answer 1

118

Question 2

What is matter?

Answer 2

The substance of which any physical object is composed of as long as the mass and dimensions of the object can be measured.

Question 3

Three characteristics of an element

Answer 3

• Consists of only one kind of atom
• Cannot be broken down into a simpler type of matter by either physical or chemical means
• Can exist as atoms or molecules

Question 4

What are the rows and columns in a periodic table called?

Answer 4

Horizontal rows are periods, vertical rows are groups

Question 5

Which sub-atomic particles are contained in the nucleus of an atom?

Answer 5

Protons and neutrons

Question 6

Proton and neutron mass

Answer 6

1.67 x 10^-27 kg

Question 7

Electron mass

Answer 7

9.11 x 10^-31 kg

Question 8

How can an atom be identified?

Answer 8

By the number of protons in the nucleus

Question 9

How does electron energy change through the shells?

Answer 9

The outer shell electrons have more energy than electrons in the inner shell

Question 10

Formula: The nth shell of an atom can generally hold how many electrons?

Answer 10

2n²

Question 11

Relationship between number of electrons in valence shell and reactivity?

Answer 11

Valence shell full = less reactive and more stable

Question 12

Electrical conductivity characteristics in relation to valence shells?

Answer 12

Less than half full = Electrical conductor
Half full= Electrical semi-conductor
More than half full = Electrical insulator

Question 13

What is an isotope?

Answer 13

A different form/variation of an element based on how many neutrons are in the nucleus

Question 14

What does the atomic number of an element tell us?

Answer 14

How many protons are in the element

Question 15

How can you calculate the number of neutrons in an element?

Answer 15

Subtract the atomic number from the atomic mass number

Question 16

What is an ion?

Answer 16

An atom or molecule with a positive or negative charge, normally by losing or gaining electrons

Question 17

What is a positive ion called?

Answer 17

Cation

Question 18

What is a negative ion called?

Answer 18

Anion

Question 19

What does a covalent bond form between?

Answer 19

Two non-metals

Question 20

In which type of bond do atoms share electrons?

Answer 20

Covalent bonds

Question 21

What do ionic bonds usually form between?

Answer 21

A metal and a non-metal. Involves electron transfer. The metal usually becomes positive

Question 22

What is a compound?

Answer 22

A pure substance made of two or more different elements chemically combined.

Question 23

Difference between a compound and a mixture?

Answer 23

The elements in a mixture are not chemically joined

Question 24

Three types of mixtures depending on particle size?

Answer 24

Solutions
Suspensions
Colloids

Question 25

What is the difference between boiling and evaporation?

Answer 25

Boiling is rapid evaporation at a fixed temperature and requires continuous addition of heat Evaporation takes place more slowly at any temperature between the melting point and boiling point

Question 26

Is evaporation and boiling endothermic or exothermic?

Answer 26

Endothermic

Question 27

Relationship between atmospheric pressure and evaporation/boiling?

Answer 27

Lower atmospheric pressure = easier to boil and evaporate i.e. lower boiling point

Question 28

Is condensation endothermic or exothermic?

Answer 28

Exothermic

Question 29

Is melting endothermic or exothermic?

Answer 29

Endothermic

Question 30

What is the name given to a phase change from a solid to a gas?

Answer 30

Sublimation

Question 31

What is the name given to a phase change from a gas to a solid?

Answer 31

Deposition