Topic 1: Safety, States of Matter and Separation techniques Flashcards
(27 cards)
the arrangement, movement and energy of the particles in a solid
-strong forces of attraction which holds them close together in a fixed positions in a lattice arrangement
- the particles dont move, they keep a definite shape and volume and dont flow
-the particles vibrate about their positions(more as they gain temperature, making them expand slightly)
the arrangement, movement and energy of particles in a liquid
-weak forces of attraction. randomly arranged and free to move over each other but tend to stick together.
-have a definite volume but flow to fill the bottom of a container
- particles are constantly moving with random motion. the hotter the liquid gets the faster they move, which causes the liquid to expand slightly.
the arrangement, movement and energy of particles in a gas
-the force of attraction is very weak between particles. they are free to move and are far apart. the particles travel in strait lines.
-dont keep a definite shape or volume and will always fill any container.
- the particles move randomly with random motion. the hotter the gas gets, the faster the particles move. gases expand when temperature or pressure increases
change from liquid to solid
freezing
- decrease in temp
- decrease in kinetic energy
- particles move less, and form bonds
change from gas to liquid
condensing
- decrease in temp
-decrease in kinetic energy
-particles lose energy and move less
change from solid to liquid
melting
-increase in temperature and kinetic energy in particles
-particles vibrate more and then they have enough energy to weaken their bonds and break from their positions
change from liquid to gas
evaporating
- increase in temp and kinetic energy in particles
-particles move faster and weakens and breaks the bonds holding the liquid together.
- at a certain temp, they fully break their bonds and turn into a gas.
change from solid to gas
sublimation
-increase in temp and kinetic energy between particles
- skip the liquid faze and turn strait to gas by breaking their bonds with enough energy
change from gas to solid
deposition
-decrease in temp and kinetic energy between particles
-skips the liquid phase and turns strait to a solid by creating bonds between particles.
dilution of coloured solutions practical
Potassium manganate(VII) and water
-potassium crystals added to beaker of water.
-the purple colour spreads out by diffusion out among the particles of water.
- this is caused by the random movement of particles in water.
-more water added would lead to the purple particles to spread out more, this is called dilution
diffusion experiments
Ammonia and hydrogen chloride
-put cotton wool soaked in aqueous ammonia at one end of a sealed glass tube and cotton wool soaked in hydrochloric acid at the other end.
- a ring of ammonium chloride forms between them.
the ring isnt in the middle because of the slower diffusion rate of the hydrochloric acid
Bromine in air
- put bromine gas(brown) in a half a test tube, separated by a glass plate.
remove the glass plate and the gas will diffuse evenly through the rest of the tube becuase of the particles random motion.
what is a solvent
the liquid something is dissolving into
what is a solute
the substance being dissolved
what is a solution
the mixture of solute and solvent that does not separate out
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
what is an atom
an atom is a single element made up of protons, neutrons and electrons.
what is a molecule
a molecule is a group of atoms.
what is an element
an element is a single type of atom
what is a compound
a substance made up of two or more different elements chemically bonded together e.g. carbon dioxide
what is a mixture
a substance made up of two or more different elements not chemically bonded together.
the element can be separated through different methods
what is simple distillation
- used for separating a liquid from a solution.
- the solution is heated and the part with the lowest boiling point evaporates.
- the vapour is collected and cooled in a condenser, then collected in a beaker
- the rest of the solution is left behind in the flask
what is fractional distillation
this is used to seperate a mixture of liquids
- the mixture is put in a flask and a frationing column is put on top.
- the liquid with the lowest boiliong point will evaporate and reach the top of the column first.
-liquids with a higher boiling point will also evaporate but the column is a lower temp than the flask so they will condense and run back down into the flask.
- you can increase the temp to separate the liquids one by one.
what is filtration
filttration is used to separate an insouble solid from a liquid
what is crystallisation
crystallisation separates a soluble solid from a solution
-evaporate of some of the water by heating to concentrate the solution
-leave the solution to cool
- crystals should form as it becomes insoluble in the cold solution.
