Particles

Question 1

Which state of matter is this?

Explain why you think this

Answer 1

This is a solid

It is a solid becuase all of the particles are touching and they are all in a regular pattern

Question 2

Which state of matter is this?

Explain how you know this

Answer 2

This is a gas

It is a gas becuase the particles are arranged randomly and are not touching each other

Question 3

Which state of matter is this?

Explain how you know this

Answer 3

This is a liquid

It is a liquid becuase the particles are aranged randomly and are all touching each other

Question 4

What does the word ‘density’ mean

Arrange the state of matter from the most to the least dense

Answer 4

Density is how packed together the particles are

Solids are the most denst becuase the particles are the most packed together

Liquids are less dense becuase the particles are a bit less packed together

Gasses are the least dense becuase the particles are very far apart

Question 5

What are the rules for how density affects floating and sinking

Answer 5

If a solid is more dense than the liquid it is in it will sink. If a solid is less dense than the liquid it is in it will float

Question 6

Why do the bubbles in a fizzy drink float to the top of the liquid?

Answer 6

The bubbles are made of gas, and gas is less dense than liquids.

Becuase the gas is less dense than the liquid it floats upwards.

Question 7

Ice is the only solid that is less dense than it’s liquid, explain what happens when you put ice in water in terms of particles.

Answer 7

When you put ice in water it will float. This is because the ice is less denst than the water, so the particles in the ice must be further apart than the particles in the water.

Question 8

What is the name for when a solid turns into a liquid?

What happens to the particles when this happens?

Answer 8

Melting

The bonds between the particles break and turn into weak bonds. The particles can then move about.

Question 9

What is the name for when a liquid turns into a solid?

What happens to the particles when this happens?

Answer 9

Freezing

The particles cannot move as much and line up, forming strong bonds between them

Question 10

What is the name for when a gas turns into a liquid?

What happens to the particles when this happens?

Answer 10

Condensation

When this happens the particles move closer together and they form weak bonds between them

Question 11

What are the two ways that we can turn a liquid into a gas?

What happens to the particles when this happens?

Answer 11

Boiling - this is when you heat it up very fast and it bubbles

Evaporation - this is when you heat it up very slowly, the gas leaves but it does not bubble

When this happens the weak bonds between the particles break so they can move around freely

Question 12

How do the particles move in a solid?

Explain why this is

Answer 12

The particles in a solid can only vibrate.

This is becuase they have strong bonds between them

Question 13

How do the particles move in a liquid

Explain why this is

Answer 13

The particles in a liquid move past each other but always have to be touching another liquid particle

This is because they have weak bonds between them. These allow them to move but do not allow them to seperate

Question 14

How do the particles move in a gas

Explain why this is

Answer 14

The particles in a gas move about very quickly and are very far apart

This is because the particles do not have any bonds between them

Question 15

The red particles are moving randomly. What is the name for this type of movement and why does it happen?

Answer 15

The movment is called Brownian motion

It happens becuase the particles bup into each other and bounce off in a random direction at a random speed

Question 16

Expalin what diffusion is

Answer 16

Diffusion is when two gasses or liquids mix becuase of the random motion of the particles

Question 17

Which state of matter is easiest to compress (squash)?

Explain why this is

Answer 17

Gasses are the easiest to compress

This is because there are large spaces between the particles in a gas so you can get them much closer together when you squash them

Question 18

What happens to the volume (size) of a subastnace when you heat it up?

Explain why this is

Answer 18

When you heat something up the volume increases (it gets bigger)

This is because the particles move about more when they get hotter so they move a bit further apart. This happens in solids, liquids and gasses

Question 19

What happens to the volume (size) of a substance when you cool it down?

Explain why this is.

Answer 19

When you cool down a substance it gets smaller (the volume decreases)

This is becuase the particles cannot move about as much so they get closer together

Question 20

Explain how a thermometer works

Answer 20

A thermometer contains a liquid. When the liquid is heated up it expands (gets bigger). This means that it moves further up the tube becuase it takes up more space.

Question 21

Explain how dissolving happens

Why can’t you see a solid once it has dissolved?

Answer 21

when something dissolves, the particles of the solvent (the liquid) smash into the particles of the solute (the solid). This breaks them apart and they mix together to form a solution

You cannot see a solid that has disolved becuase the particles are sepearate and too small to see

Question 22

What do the words solvent, solute and solution mean?

Answer 22

A solution is when a solid is dissolved in a liquid

The solvent is the liquid that the solid dissolves in (for example water)

The solute is the solid that can dissolve in the liquid (for example salt or sugar)

Question 23

What is a saturated solution?

Answer 23

A saturated solution is a solution where there is so much solid (solute) dissovle in it that you cannot dissolve any more in

Question 24

Explain what the word solubility means

Answer 24

Solublility means how well a solid can dissolve in a liquid. the more soluble something is, the more of it can dissolve in the liquid

Question 25

How does a gas cause pressure?

Answer 25

A gas has pressure becuase the particles collide into the side of the container, pushing outwards. There is more pressure if there are more particles colliding, or if the particles are hotter (so they are moving faster)

Question 26

Explain what the melting point is

Answer 26

The melting point is the temperature that a substance changes betwen a solid and a liquid.

If a substance is colder than it’s melting point it is a solid

If a substance is between the melting point and boiling point it is a liquid

Question 27

Explain what the boiling point is

Answer 27

The boiling point is the temperature that something changes from a liquid to a gas.

If a substance is between the boiling point and melting point it is a liquid

If a substance is warmer than its boiling point then it is a gas