Particles and Formulae

Question 1

What are all things made of?

Answer 1

Particles

Question 2

What are the three states of matter?

Answer 2

Solids, liquids and gases

Question 3

Draw the particle diagram for a solid.

Answer 3

Diagram

Question 4

Draw the particle diagram for a liquid.

Answer 4

Diagram

Question 5

Draw the particle diagram for a gas.

Answer 5

Diagram

Question 6

Describe the arrangement of particles in a solid.

Answer 6

Regular arrangement, particles are touching

Question 7

Describe the arrangement of particles in a liquid.

Answer 7

Random arrangement, particles are touching

Question 8

Describe the arrangement of particles in a gas.

Answer 8

Random arrangement, particles are not touching

Question 9

Describe the motion of particles in a solid.

Answer 9

Vibrate in a fixed position.

Question 10

Describe the motion of particles in a liquid.

Answer 10

Able to move past each other.

Question 11

Describe the motion of particles in a gas.

Answer 11

Move in random directions at random speeds.

Question 12

Give two properties of solids

Answer 12

They don’t flow (fixed shape)
They can’t be compressed (fixed volume)

Question 13

Explain why solids cannot flow

Answer 13

The particles are in a fixed position due to strong forces of attraction between particles.

Question 14

Explain why solids cannot be compressed

Answer 14

There is no space between particles.

Question 15

Give two properties of liquids

Answer 15

They can flow (take the shape of their container)
They can’t be compressed (fixed volume)

Question 16

Explain why liquids can flow

Answer 16

The particles are free to move past each other.

Question 17

Explain why liquids cannot be compressed

Answer 17

There is no space between particles.

Question 18

Give two properties of gases.

Answer 18

They can flow (spread out to fill their container)
They can be compressed (can change volume)

Question 19

Explain why gases can flow

Answer 19

The particles are free to move past each other.

Question 20

Explain why gases can be compressed

Answer 20

There is space between the particles.

Question 21

What happens in a change of state?

Answer 21

The particles change arrangement due to an increase or decrease in thermal energy

Question 22

What is the name for the process of solids turning to liquids?

Answer 22

Melting

Question 23

What is the name for the process of liquids turning to gases?

Answer 23

Boiling (or evaporation)

Question 24

What is the name for the process of gases turning to liquids?

Answer 24

Condensing

Question 25

What is the name for the process of liquids turning to solids?

Answer 25

Freezing

Question 26

What is the melting point of a substance?

Answer 26

The temperature at which it melts or freezes

Question 27

What is the boiling point of a substance?

Answer 27

The temperature at which it boils or condenses

Question 28

What happens to the particles in a substance when it is heated up?

Answer 28

They move faster

Question 29

State one similarity and one difference between boiling and evaporation?

Answer 29

Similarity: both a state change from liquid to gas Difference: Evaporation occurs at any temperature between melting and boiling points, boiling occurs at the boiling point of the substance.

Question 30

What is the melting point of water?

Answer 30

0°C

Question 31

What is the boiling point of water?

Answer 31

100°C

Question 32

Approximately what is room temperature?

Answer 32

20°C

Question 33

If I have a substance with a melting point of -98°C and a boiling point of -10°C, what state will it be at room temperature?

Answer 33

Gas, as 20°C is above the boiling point.

Question 34

If I have a substance with a melting point of 120°C and a boiling point of 380°C, what state will it be at room temperature?

Answer 34

Solid, as 20°C is below the melting point.

Question 35

If I have a substance with a melting point of -58°C and a boiling point of 232°C, what state will it be at room temperature?

Answer 35

Liquid, as 20°C is between the melting and boiling points.

Question 36

What is diffusion?

Answer 36

The movement of particles from an area of high concentration to an area of low concentration

Question 37

How does temperature affect diffusion?

Answer 37

An increase in temperature increases the rate of diffusion.

Question 38

How does concentration affect diffusion?

Answer 38

A higher concentration gradient (difference) increases the rate of diffusion.

Question 39

What is an element

Answer 39

A substance made of only one type of atom

Question 40

What is an atom

Answer 40

The smallest part of an element that can exist

Question 41

What are subatomic particles?

Answer 41

Particles smaller than an atom which combine together to make atoms.

Question 42

What is the most of an atom made up of?

Answer 42

Empty space

Question 43

What is the name of the centre of the atom where almost all of the mass is held?

Answer 43

The nucleus

Question 44

Where are electrons located in the atom?

Answer 44

In shells (energy levels) around the nucleus.

Question 45

Name parts A, B and C

Answer 45

A - Proton B - Neutron C - Electron

Question 46

What is the mass and charge of a proton?

Answer 46

Mass = 1 amu Charge = +1 (positive)

Question 47

What is the mass and charge of a neutron?

Answer 47

Mass = 1 amu Charge = 0 (neutral)

Question 48

What is the mass and charge of an electron?

Answer 48

Mass = 0.0005 amu (almost zero) Charge = -1 (negative)

Question 49

How many electrons can the first shell hold before the second shell starts to fill?

Answer 49

2 (The same number as the number of elements in the first row of the periodic table)

Question 50

How many electrons can the second shell hold before the third shell starts to fill?

Answer 50

8 (The same number as the number of elements in the second row of the periodic table)

Question 51

How many electrons can the third shell hold before the fourth shell starts to fill?

Answer 51

8 (The same number as the number of elements in the third row of the periodic table)

Question 52

What is the atomic number?

Answer 52

The number of protons in the nucleus and the number that defines what element an atom is from

Question 53

What is the mass number?

Answer 53

The number of protons and neutrons in an atom.

Question 54

In a neutral atom, what is the electron number equal to?

Answer 54

Atomic (proton) number

Question 55

Give the number of protons, neutrons and electrons in this element:

Answer 55

Protons: 8 Neutrons: 15 - 8 = 7 Electrons: 8

Question 56

Give the number of protons, neutrons and electrons in this element:

Answer 56

Protons: 11 Neutrons: 23 - 11 = 12 Electrons: 11

Question 57

What is the chemical symbol for hydrogen?

Answer 57

H

Question 58

What is the chemical symbol for helium?

Answer 58

He

Question 59

What is the chemical symbol for carbon?

Answer 59

C

Question 60

What is the chemical symbol for oxygen?

Answer 60

O

Question 61

What is the chemical symbol for sodium?

Answer 61

Na

Question 62

Why do some elements have chemical symbols which are not the first two letters of their name?

Answer 62

Some symbols represent other languages. Some elements have similar starts to their names.

Question 63

How many capital letters are there in a chemical symbol?

Answer 63

One capital letter. Some symbols also have a lower case letter after the capital letter.

Question 64

What is the difference between a physical and chemical change?

Answer 64

Physical change is a change in the state of a substance, nothing new is made. A chemical change involves at least one new substance being made and is usually not easily reversed.

Question 65

State five signs of a chemical reaction.

Answer 65

Colour change Temperature change Gas given off (effervescence) Odour (smell) change Solid (precipitate) formed

Question 66

What is the name for substances that react together in order to produce something new?

Answer 66

Reactant(s)

Question 67

What is the name for the new substances that are formed by a chemical reaction?

Answer 67

Product(s)

Question 68

What symbol is used in a chemical reaction equation to show a reaction has taken place?

Answer 68

An arrow (going from the reactants to the products)

Question 69

What is a compound?

Answer 69

A substance made of two or more elements chemically bonded together.

Question 70

State the rules for naming compounds made of two elements.

Answer 70

Start with the name of the metal (if there is one) The ending of the non-metal is changed to -ide

Question 71

State the rules for naming compounds with three elements where one of them is oxygen.

Answer 71

Start with the name of the metal (if there is one) Don’t include “oxygen” in the name. The ending of the non-metal is changed to -ate

Question 72

What compound is formed when lithium bonds with chlorine?

Answer 72

Lithium chloride

Question 73

What compound is formed when calcium bonds to carbon and oxygen?

Answer 73

Calcium carbonate

Question 74

Define molecule

Answer 74

Two or more atoms, chemically bonded into a single particle.

Question 75

Does a molecule have to be a compound?

Answer 75

No, a molecule can be an element made of more than one of the same type of atom chemically bonded together into a single particle.

Question 76

Define (chemically) pure

Answer 76

When a substance is made of only one element or compound.

Question 77

Define (chemically) impure

Answer 77

When a substance is made of more than one substance not chemically bonded together.

Question 78

What is a mixture?

Answer 78

An impure substance that can be separated by physical (not chemical) processes.

Question 79

Is spring water pure? Explain your answer.

Answer 79

No. Spring water contains minerals which are not chemically bonded to the water molecules.

Question 80

Is air pure? Explain your answer.

Answer 80

No. Air contains a mixture of elements and compounds in their gaseous state which are not chemically bonded.