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Flashcards in STATES OF MATTER Deck (26)
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1

What processes provides evidence to support that all matter is made up of particles?

Diffusion and osmosis provides the evidence for the particulate theory of matter.


Matter is anything that has mass and volume (occupies space). Matter itself exists in 3 states.

solids, liquids, gases
Particles are in a state of random motion dependent on kinetic E. The higher the temperature of the particles, the more kinetic E the particles will have and the faster they will move.

2

What is The Particulate Theory of Matter?

The Particulate Theory of Matter states that
1. All matter is composed of particles.
2. The particles are in constant motion and temperature affects their speed of motion.
3. The particles have empty spaces between them.
4. The particles have forces of attraction between them.

3

How can you prove that particles have space between them?

Intermolecular space is the space between two molecules or atoms. In solids, it is very little. In liquids the space is more than that in solids and in gas, it is maximum.


Take a glass of water, add sugar and stir. You will observe that there is no rise in the water level. This shows that particles of matter have spaces between them. When sugar is added to the water, the sugar particles adjust themselves in the space between the water particles.

4

What is diffusion?

Diffusion is the net movement of particles from a region of higher concentration to a region lower concentration until the particles are evenly distributed.

5

What is osmosis?

Osmosis is the movement of water molecules through a differentially permeable membrane from a dilute solution (a solution containing a lot of water molecules) to a concentrated solution (a solution containing fewer water molecules).


When a dilute sucrose solution is separated from a concentrated sucrose solution by a differentially permeable membrane, water molecules move through the membrane from the dilute solution into the concentrated solution, but the sucrose molecules cannot move in the other direction. The volume of the concentrated solution increases and the volume of the dilute solution decreases.

6

What is brownian motion?

Brownian motion is the irregular movement of pollen grains suspended in water.


Air and water particles are constantly moving and consistently collide with the pollen grains causing them to move in an irregular way.

7

What are 2 examples and 2 experiments of diffusion?

1. Cooking aroma
2. The smell of flowers


1. When pieces of cotton wool soaked in concentrated ammonia solution and concentrated hydrochloric acid are placed simultaneously at opposite ends of a glass tube, a white ring of ammonium chloride forms inside the tube. Ammonia solution gives off ammonia gas and hydrochloric acid gives off hydrogen chloride gas. The particles of the gases diffuse through the air inside the tube, collide and react to form ammonium chloride:

ammonia + hydrogen chloride • ammonium chloride

NH3(g) + HCI(g) • NH4CI(s)

Ammonia particles diffuse faster than hydrogen chloride particles, so the particles collide and react closer to the source of the hydrogen chloride particles.

The ring is not at the centre of the tube because smaller lighter particles like ammonia travel faster than larger heavier particles like hydrogen chloride. Ammonia has a lower density than hydrogen chloride. Therefore ammonia diffuses at a faster rate.

2. When a purple potassium manganate(VII) crystal is placed in water, it dissolves to produce a uniformly purple solution. The particles making up the crystal separate from each other and diffuse through the spaces between the water particles until they are evenly distributed.

Dialysis is a process used to remove wastes from the blood of patients who suffer from kidney failure. A dialysis machine works on the principle of diffusion.

8

What is 1 experiment that shows the process of osmosis?

The membranes of living cells are differentially permeable and the cytoplasm inside the cells contains about 80% water.


When a strip of living tissue (such as paw-paw) is placed in water, water molecules move into the cells by osmosis. Each cell swells slightly, and the strip increases in length and becomes rigid. When the strip is placed in a concentrated sodium chloride solution, water molecules move out of the cells by osmosis. Each cell shrinks slightly, and the strip decreases in length and becomes softer.

9

What are two uses of osmosis?

1. To control garden pest - garden pests like slugs and snails have skin that is differentially permeable and always moist. When salt (sodium chloride) is sprinkled on slugs and snails, it dissolves in the moisture around their bodies forming a concentrated solution. Water inside their bodies then moves out by osmosis and into the solution. The slugs and snails die from dehydration if their bodies lose more water than they can tolerate.


2. To preserve food - salt and sugar are used to preserve foods such as meat, fish and fruit. They draw water out of the cells of the food by osmosis. This prevents the food from decaying because there is no water available in the cells for the chemical reactions which cause the decay. They draw water out of microorganisms (bacteria and fungi) by osmosis preventing the food from decaying because it inhibits the growth of these microorganisms that cause the decay.

10

How can a solid be described based on the following properties?
shape

volume
density
compressibility
arrangement of particles
forces of attraction between the particles
energy possessed by the particles
movement of the particles

The shape and volume is fixed. The density of a solid is usually high. It is difficult to compress. The arrangement of particles are packed closely together, usually in a regular way. The forces of attraction between the particles are strong and a solid possess very small amounts of kinetic energy. Solids vibrate in their fixed position.

11

How can a liquid be described based on the following properties?
shape

volume
density
compressibility
arrangement of particles
forces of attraction between the particles
energy possessed by the particles
movement of the particles

Liquids take the shape of the part of the container it is in and the surface is always horizontal. The volume of a liquid is fixed and its density is usually lower than solids. Liquids can be compressed very slightly by applying pressure. Liquids have small spaces between and are randomly arranged. The forces of attraction between the particles are weaker than those between the particles in a solid. Liquids possess more kinetic energy than the particles in a solid and the particles move slowly past each other.

12

How can a gas be described based on the following properties?
shape

volume
density
compressibility
arrangement of particles
forces of attraction between the particles
energy possessed by the particles
movement of the particles

Gases take the shape of the entire container it is in. The volume is variable meaning it expands to fill the container it is in. The density of a gas is low and gases are very easy to compress. The particles have large spaces between and are randomly arranged. The forces of attraction between the particles are very weak. Gases possess large amounts of kinetic energy and the particles move around freely and rapidly.

13

How can the changes between the three states of matter in terms of energy and arrangement of particles be explained?

Temperature


Matter can exist in any of the three states depending on its temperature. It can change from one state to another by heating or cooling, as this causes a change in the kinetic energy and arrangement of the particles.

During melting its temperature remain constant even though heat is continually supplied. This is because during melting heat energy is absorbed by the particles of the solid to overcome the force of attraction. After all the solid particles have changed into a liquid state, further heating will cause the particles to gain kinetic energy and raise their temperature.

14

What happens when a solid is heated?

It changes state to a liquid and then to a gas. This occurs because the particles gain kinetic energy, move increasingly faster and further apart, and the forces of attraction between them become increasingly weaker.

15

What happens when a gas is cooled?

It changes state to a liquid and then to a solid. This occurs because the particles lose kinetic energy, move more and more slowly and closer together, and the forces of attraction between them become increasingly stronger.

16

What is evaporation?

Evaporation is the change of state from a liquid into a gas without heating.


Evaporation occurs at any temperature below its boiling point and takes place only at the surface of a liquid. Evaporation produces a cooling effect as heat is absorbed from its surroundings.

17

What is the difference between evaporation and boiling?

Evaporation can take place at any temperature, whereas boiling occurs at a specific temperature. Evaporation takes place at the surface of the liquid only, whereas boiling takes place throughout the liquid.

18

When can Evaporation take place?

at any temperature
Evaporation takes place at the surface of the liquid only.

19

When can Boiling occur?

only at a specific temperature
Boiling takes place throughout the liquid

20

What is condensation/deposition?

The change of state from a gas to a liquid.


Condensation — heat energy is given out as the gas particles slow down and move closer to one another to form a liquid

21

What is sublimation? What are three examples of substances that sublime?

The change of state from a solid directly into a gas.


carbon dioxide (dry ice)
iodine
naphthalene (moth balls)

Sublimation — heat energy is absorbed when a solid sublimes.

22

What is melting point?

The melting point is the constant temperature at which a solid changes state into a liquid.


Melting — heat energy is absorbed to break down the force of attraction on its temperature

23

What is boiling point?

The boiling point is the constant temperature at which a liquid changes state into a gas.


Boiling — heat energy is absorbed to overcome the force of attraction between the liquid particles and make them move far apart.

24

What is freezing point?

The freezing point is the constant temperature at which a liquid changes state into a solid.


Freezing — heat energy is given out as the particles slow down and move closer to take up fixed and orderly positions in a solid.

25

What is a heating curve?

A heating curve is drawn when the temperature of a solid is measured at intervals as it is heated and changes state to a liquid and then to a gas, and the temperature is plotted against time.

26

What is a cooling curve?

A cooling curve is drawn when the temperature of a gas is measured at intervals as it is cooled and changes state to a liquid and then to a solid, and the temperature is plotted against time.