States of Matter and solubility chemistry Flashcards
What are the 3 states of matter?
- solid
- liquid
- gas
What is the force of attraction like in a solid?
- strong forces of attraction between particles
- which holds them close together in fixed positions
- to form a regular lattice arrangement
Why do solids keep a definite shape and volume?
- particles don’t move from their positions
- instead particles vibrate around their positions
What is the force of attraction like in a liquid?
- weak force of attraction between particles in a liquid
How are the particles in a liquid arranged?
- randomly arranged and free to move past each other
- but they tend to stick closely together
Why will liquids flow to the bottom of the container?
- they have a definite volume
- but not a definite shape
How do the particles move in a liquid?
- constantly moving with random motion
- hotter the liquid gets, the faster they move
- causing liquids to slightly expand when heated
What is the force of attraction like between particles in a gas?
- force of attraction is very weak
How do particles move around in a gas?
- free to move and are far apart
- particles travel in straight lines
- move constantly in a random motion
What is the change in state from a solid to a liquid?
- melting
- at certain temperatures the particles have enough energy to break free from their positions
What is the change in state from a solid to a gas?
- subliming
What is the change in state from a liquid to a gas?
- evaporating
- at certain temperatures the particles have enough energy to break their bonds
What is the change in state from a gas to a liquid?
- condensing
What is the change in state from a liquid to a solid?
- freezing
What is diffusion?
- the gradual movement of particles from place where there are lots of them
- to places where there are fewer of them
How do you test for diffusion using potassium manganate and water?
- take a beaker of water and place some potassium manganate at the bottom
- the purple colour slowly spreads out to fill the beaker
- the particles of potassium manganate are diffusing out amongst the particles of water
- its the random motion of particles in a liquid that causes the purple colour to eventually spread out through the water
How can you describe dilution with the potassium manganate experiment?
- add more water to the final purple solution
- potassium manganate particles would spread even further apart and the solution would become less purple
- this is called dilution
How can you carry out diffusion with ammonia and hydrogen chloride?
- NH3 gas diffuses from one end of the tube and the HCl gas diffuses from the other
- when they meet, they react to from ammonium chloride
- the ring forms nearest the end of the tube where the HCl was
In the ammonia and hydrogen chloride experiment, why does the ring form nearest the end of the tube where the HCl was?
- particles of ammonia are smaller and lighter than the particles of hydrogen chloride
- so they diffuse through the air more quickly
How can you demonstrate diffusion with bromine gas and air?
- bromine gas is a brown strong smelling gas
- fill half a gas jar of bromine gas
- and the other half full of air
- separate the gases with a glass plate
In the bromine gas and air experiment, what can you observe when you remove the glass plate?
- you will see the brown bromine gas slowly diffusing through the air
- the random movement of particles means that the bromine will eventually diffuse right through the air
What is a solution?
- mixture of a solute and a solvent that does not separate out
What is a solute?
- is the substance being dissolved
What is a solvent?
- is the liquid its dissolving into
What is a saturated solution?
- a solution where the maximum amount of solute has been dissolved, so no more solute will dissolve in the solution
How can you calculate solubility?
solubility= mass of solid/mass of water removed X 100
How can you investigate how temperature affects solubility?
- make a saturated solution by adding excess ammonia chloride to 10cm3 of water in a boiling tube
- you will know when ammonium chloride is in excess because it sinks to the bottom of the tube
- give the solution a good stir and place the boiling tube in a water bath at 25 degrees
- after 5 minutes check the excess solid has sunk to the bottom with a thermometer
- weigh an evaporating basin
- pour solution into basin
- re weigh basin
- gently heat using a Bunsen burner (removes water)
- evaporation occurs and you are left with ammonium chloride
- reweigh evaporating basin
- repeat steps 1-6 mire time but with the water bath at different temperatures
