All of year 9 Flashcards
What are the 3 states of matter
liquid
solid
gas
what does each sate of matter depend on
how strong the forces of attraction are between the particles of the material
descirbe the arrangement in solids and why
very regular because of the strong forces of attraction holding them together
describe the movement of solid particles
they don’t move but do vibrate about a fixed point whilst keeping a definite shape and volume
what happens when materials are heated
the particles vibrate/move more gaining energy causing the material to expand
describe the arrangement and movement of liquids
weak forces of attraction cuase the particles to be random and free to move over each other and fill the bottom of the container
desribe the arrangement of gas particles
very weak forces allow the particles to be free to move and be far apart filling any container
What happens when gases are heated
they either expand or the pressure is increased
what is the process where a solid becomes liquid
melting
what is the process where a liquid becomes a solid
freezing
what is the process where a liquid becomes a gas
evaporating
what is the process where a gas becomes a liquid
condensing
what is the process where a solid becomes a gas
subliming
what is diffusion
the gradual movement of gas or liquid particles from places where there are lots to places where there are fewer
In a diffusion experiment with ammonia and hyrogen chloride why is the ring of ammonium chloride not in the center
becuase the hydrogen chloride particles are denser than the ammonium particles - they take longer to move
what is a solution
a mixture of solvent and solute that does not seperate out
what is a solute
the substance being dissolved
what is a solvent
the liquid the solute dissolves into
what is a saturated solution
a solution where the maximum amount of solute has been dissolved
what is solubility
the measure of how much solute will dissolve in 100g of solvent
how do you calculate solubility
(mass of solid / mass of water removed) x 100
How can you investigate how temperture affects solubility
- weigh empty evaporating basin
- pour some solution in basin
- re-weigh basin
- heat with bunsen burner
- re-weigh pure substance once water evaportated
define isotope
isotopes are different atomic forms of the same element, which have the same number of protons but a different number of neutrons
what does the atomic number of an element tell you
how many protons
how can you find out the group number of an element
the number of electrons on the outer shell
how can you find out the period of an element
the number of occupied shells
what is an element
an element consists of only one atom
what is a compound
compounds are chemically boned elements (two or more)
what is a mixture
mixtures are easily seperated: there is no chemical bond
how can you tell if something is a pure substance
because it will have a speecific, sharp melting and boiling point
What is filtration used for
to seperate an insoluable solid from a liquid
what is crystallisation used for
to seperate a soluable solid from a solution
what do you need to perform filtration
beaker
funnel
filter paper
what is the mixture that stays in the filter paper call
the residue
how does crystallisation work
- pour mixture into evapourating dish
- heat solution ~ water will evapourate
- once water evaporated leave dish to cool and dry
why does chromatography work when seperating mixtures
becuase dyes in the mixture move up the paper at different rates
how do you preform chromotagraphy
- draw base line wiht pencil
- add spots of ink to baseline
- loosely roll paper and put in beaker with some water (ensure the baseline is above water level)
- once dyes have spread take out to dry
how do you calculate the Rf value
distance travelled by solute / distance traveled by solvent