Presentation on theme: "Matter is made up of extremely tiny particles. These tiny particles may be molecules or ions. Molecules of the same substances are the same. Molecules."— Presentation transcript:
Matter is made up of extremely tiny particles. These tiny particles may be molecules or ions. Molecules of the same substances are the same. Molecules of different substances are different. A model of water dioxide A model of carbon dioxide
Gas particles are very far apart from each other. They move at high speeds.
Liquid particles are much closer. They are moving continuously.
Solid particles are close together in a regular pattern. They cannot move from one place to another place. Solid particles are vibrating about their positions all the time.
To show that ammonia molecules and hydrochloric acid molecules are moving. Procedure 1. Set up the apparatus as shown above. 2. Leave the apparatus for some time and observe.
To show that ammonia molecules and hydrochloric acid molecules are moving. Result
To answer the questions on the next page, you must imagine that the gases are made of tiny particles
Ammonia solution White fumeHydrochloric acid Form white fume yes No It takes a shorter time to form the white fume because... Particles move faster at higher temperature What happens when the hydrochloric acid particles met the ammonia particles? Are the particles of the two substances moving? Do they move at the same speed? If the whole glass tube is warmed, do you think it takes a longer or shorter time for any change to be seen?
Ammonia solution White fumeHydrochloric acid The above experiment shows that both ammonia and hydrochloric acid diffuse.
Diffusion is the spreading out of a substance. Why does diffusion occur? Particles of matter move from one place to other places. Is the rate of diffusion equal to the speed of moving particles? The speed of diffusion is much smaller Why? Collision between the particles slows down diffusion rate. The possible path of a gas particle
Procedure 1. Place 2 drops of bromine into the gas jar and cover it immediately. 2. Observe how the bromine spreads by noting the colour. Question 1. How far has the bromine spread? 2. Can you explain how the bromine diffuses (spreads)? bromine liquid gas jar cover
Procedure 1. Place a copper sulphate crystal into 75 cm 3 of cold water. 2. Place another piece into the same volume of hot water. 3. Leave the two beaker for about 20 minutes and observe. beaker water copper sulphate crystal
Question 1. Why did we use a coloured solid? 2. Had diffusion of the coloured solid particles occurred? 3.Is diffusion faster in cold water or hot water? 4. Is diffusion faster in a liquid or in gas? 1. We can observe the diffusion of a coloured matter. Yes Diffusion is faster in hot water Diffusion is faster in liquid
SolidLiquid Gas Example IceWater Steam
SolidLiquid Gas Heat energy is given to solid particles which then move faster Heat energy is taken away from liquid particles which then move slower Heat energy is given to liquid particles which then move faster Heat energy is taken away from gas particles which then move slower