Chap 2: Matter and the Atomic Structure

Question 1

What is matter made up of?

Answer 1

Matter is made up of very tiny and discrete particles.

Question 2

What is matter?

Answer 2

Matter is anything that occupies space and has mass.

Question 3

In what state can matter exist in?

Answer 3

Solid, liquid or gas.

Question 4

What caused the change in the states of matter?

Answer 4

The change in the states of matter is caused by heating or cooling.

Question 5

Explain simply what happen when solid is heated.

Answer 5

When a solid is heated, it absorbs heat energy and changes from solid to liquid and finally to gas.

Question 6

Explain simply what happen when gas is cooled.

Answer 6

When a gas is cooled, it loses energy and changes to liquid and finally to solid.

Question 7

What are the properties of matter?

Answer 7

1. Arrangement of particles
2. Attraction force between particles
3. Kinetic energy or particles

Question 8

How are the particles arranged when in solid?

Answer 8

The particles are arranged in a orderly manner and are packed closely together. The spaces between the particles are very small.

Question 9

How are the particles arranged in liquid?

Answer 9

The particles are arranged disorderly manner and packed slightly loose. Most particles are still in contact with one another.

Question 10

How are the particles arranged in gas?

Answer 10

The particles are randomly arranged and are very far apart from each other.

Question 11

How is the attraction force between particles in solid?

Answer 11

Very strong

Question 12

How is the attraction force between particles in liquid?

Answer 12

Strong but weaker than the forces in solid.

Question 13

How is the attraction force between particles in gas?

Answer 13

Very weak

Question 14

How is the kinetic energy of particles in solid?

Answer 14

Low kinetic energy

Question 15

How is the kinetic energy of particles in liquid?

Answer 15

The kinetic energy is higher than in solid but is lower than in gas.

Question 16

How is the kinetic energy of particles in gas?

Answer 16

Very high kinetic energy

Question 17

What will happen when matter absorbs heat energy?

Answer 17

When a matter absorbs heat energy, the kinetic energy of its particles increases. As a result, the particles will move faster.

Question 18

What will happen when matter releases heat energy?

Answer 18

When a matter releases heat energy, the kinetic energy of its particles decreases. As a result, the particles will move slower.

Question 19

Describe the reaction of matter during the melting process.

Answer 19

• When a solid is heated, the particles in the solid gain energy. The kinetic energy of the solid particles increases and they vibrate faster.
• As the temperature increases, the particles vibrate faster until the energy absorbed is enough to overcome the attraction force that hold them at their fixed positions. At this point, the particles can move freely and the solid becomes a liquid.
• The temperature at this point is called the melting point.

Question 20

Describe the reaction of matter during the boiling process.

Answer 20

• When a liquid is heated, the particles in the liquid gain more energy. The kinetic energy of the liquid particles increases and they move faster.
• As the temperature increases, the particles move faster until the energy absorbed is enough to overcome the attraction force that hold them at the liquid state. At this point, the particles can move randomly and far apart to become gas.
• The temperature at this point is called the boiling point.

Question 21

Describe the reaction of matter during the freezing process.

Answer 21

• When a liquid is cooled, the particles lose their energy. The kinetic energy of the liquid particles decreases and they move slower.
• As the temperature decreases, the particles continues to lose energy and move closer to one another. Stronger attraction force are between particles are formed and finally the particles are arranged in orderly in their fixed positions. At this point, the liquid becomes a solid.
• The temperature at this point is called the freezing point.

Question 22

Describe the reaction of matter during the condensation process.

Answer 22

• When gas is cooled, the particles in the gas lose their energy. The kinetic energy of the gas particles decreases and their movements slow down.
• As the temperature decreases, the particles continue to lose energy and stronger attraction force between the particles are formed which pull the particles closer to each other. When the movement of the particles slow enough and the particles become very close, the gas changes to liquid.

Question 23

What is sublimation?

Answer 23

Sublimation is the process where a solid changes to its gaseous state without going through liquid state when heat is applied to it.

Question 24

What is deposition?

Answer 24

Deposition is the transition of gas to solid state on cooling without going through liquid state.

Question 25

What is an element?

Answer 25

- Element consists of only one type of atom. - All elements are made up of particles of atoms or molecules.

Question 26

What is a compounds

Answer 26

- A compound contains two or more elements that are chemically bonded together. - All compounds are made up of molecules or ions.

Question 27

According to the heating curve of naphthalene, what happen in AB?

Answer 27

- When naphthalene is heated, its particles absorbs heat energy. - It will cause the particles to gain kinetic energy. - The particles vibrate faster. - The temperature increases from point A to B.

Question 28

According to the heating curve of naphthalene, what happen in BC?

Answer 28

- At point B, the naphthalene starts to melt. - Heat energy absorbed by the particles is used to overcome the attraction force between the particles so that the solid can turn into liquid. (not to increase the kinetic energy of the particles) - Temperature of the naphthalene remains constant even though heating continues. - At this temperature, both solid and liquid are present. - At point C, naphthalene has melted.

Question 29

According to the heating curve of naphthalene, what happen in CD?

Answer 29

- From point C to D, the liquid naphthalene is heated continuously. - The liquid particles absorb heat energy. It will cause the particles to gain kinetic energy and move faster. - Temperature increases from point C to D.

Question 30

According to the cooling curve of naphthalene, what happen in PQ?

Answer 30

- From point P to Q, the liquid naphthalene is cooled continuously. - Liquid particles lose heat energy to the surroundings. It will cause the particles to lose kinetic energy and move slower. - Temperature decreases from point P to Q.

Question 31

According to the cooling curve of naphthalene, what happen in QR?

Answer 31

- At point Q, the liquid starts to freeze. - During the freezing process, the particles liberate heat energy as the particles attract one another to form solid. - At the same time, the liquid also loses heat to the surroundings. - The heat lost to the surrounding is exactly balanced by the heat energy liberated as the particles attract one another to form stronger attraction force so that the liquid can turn into solid. - Temperature of the naphthalene remains constant even though cooling continues. - This constant temperature is called the freezing point of the substances. - At this temperature, both liquid and solid are present.

Question 32

According to the cooling curve of naphthalene, what happen in RS?

Answer 32

- From point R to S, the solid naphthalene is cooled continuously. - Solid particles lose heat energy to the surroundings. - It will cause the particles to lose kinetic energy and move slower. - Temperature decreases from point R to S.

Question 33

What does it means by melting point?

Answer 33

Melting point is the temperature at which the substance at its solid state changes to liquid state at certain pressure.

Question 34

What does it means by boiling point?

Answer 34

Boiling point is the temperature at which the substance at its liquid state changes to gaseous state at certain pressure.

Question 35

What does it means by freezing point?

Answer 35

Freezing point is the temperature at which the substance at its liquid state changes to solid state at certain pressure.