P1 1a states of matter Flashcards
what are the particles in a solid like?
closely packed in a regular arrangement, no gaps between them
- only movement is vibration
do solids have strong or weak forces of attraction?
strong forces of attraction
what are the particles in a liquid like?
still close together with minimal gaps, random arrangement
- the particles can move freely but they stay touching
do liquids have strong or weak forces of attraction?
not as strong as solids because they are able to move
what are the particles in a gas like?
gas particles move wherever as they are separated, random arrangement
- absolute free movement
do gases have strong or weak forces of attraction?
no forces of attraction
what happens if you heat a solid?
a solid will melt into a liquid
- energy makes the particles vibrate more and more, eventually the forces of attraction aren’t strong enough to hold the particles together
what happens if you cool a liquid?
it will freeze and become a solid
- particles move more slowly as they loose energy and the forces of attraction will strengthen making it become a solid
what happens if you heat a liquid?
it boils or evaporates into a gaseous state
- the particles gain energy from the heat and move fast enough to completely break forces of attraction
what happens if you cool a gas?
it condenses, of turns back into a liquid
- particles will lose heat energy and therefore move slow enough for forces of attraction to hold them together as a liquid
what is a melting point?
the temp in which a solid turns into a liquid
what is a boiling point?
the temp that turns a liquid into a gas
what is a freezing point?
the temp where the liquid turns into a solid
what is sublimation?
when a solid becomes a gas straight away
what is diffusion?
it is the spreading of gases in the air
- air and bromine gas move randomly and there are large gaps between that allow for mixing
- for example a smell from one side of the room will diffuse to the other but it will take some time
what is the difference between evaporation and boiling?
evaporation only occurs at the surface of the liquid, and the gas particles will cool
- boiling is fast, produces lots of bubbles
how fast can diffusion happen?
lighter particles are faster, bigger ones are slower
what is diffusion in liquids?
when particles diffuse they do so from a region of high concentration to a region of low concentration
what happens to the concentration of a liquid when diffusion occurs?
- at the start and around the thing that is being diffused it has a very high concentration
- concentration will decrease the longer the particles are left to evenly spread
- after hours an equilibrium is reached
why is diffusion in liquids slower?
the particles in a liquid are closely packed together and move more slowly
what is dilution?
it is the addition of a solvent, which decreases the concentration of the solute in the solution
- when something is diluted and the colour does not fade there must be lots of particles in a small amount of the element (particles will be small)
what is a solute?
the substance which dissolves in a liquid to form a solution
- salt in sea water
what is a solvent?
the liquid in which a solute dissolves
- water in sea water
what is concentration?
the amount of solute and how much there is in the solvent, gets weaker as more solvent is added
what is a solution?
the mixture formed when a solute is dissolves in a solvent
- seawater
what is a saturated solution?
a solution with the maximum concentration of solute dissolved in the solvent
- seawater in the Dead Sea
what is meant by soluble?
a substance that will dissolve
what is meant by insoluble?
a substance that will not dissolve
what is solubility?
a measurement of how much of a substance will dissolve in a given volume of liquid
how is solubility expressed?
in g/100g of solvent
what effects solubility?
as temperature increases - solids become more soluble - gases become less as pressure increases - gases become more soluble
if 10g is the maximum amount of solute that dissolves in 100ml of solvent (before it gets saturated) what is the solubility?
10g/100ml
if 10g is the maximum amount of solute that dissolves in 50ml of solvent (before it gets saturated) what is the solubility?
20g/100ml
how do you figure out the solubility of a solid in water at a specific temperature?
- set water bath to the specific temperature
- measure a specific volume of water using measuring cylinder and put in a beaker (100ml)
- place beaker in water bath, and monitor the temp until it reaches the specific temp
- add known mass of solid and stir until dissolved
- keep adding known masses (small bits at a time) until no more solid dissolves, then note the amount dissolved
do protons have a positive or negative charge?
positive, relative mass of 1, +1 charge
do neutrons have a positive or negative charge?
neutral charge, relative mass of 1
do electrons have a positive or negative charge?
negative, -1 charge
what happens when there are different numbers so protons and electrons (lose or gain electrons) ?
the atom would become an ion