Chemistry

solid
is hard to compress as molecules are held tightly together by bonds
liquids
difficult to compress as there is only a small space between molecules
gases
easy to compress as moving around faster
thermometer
works as the bulb expands easily pushing liquid up the thin tube
rails
have expansion joints so they don’t bend in the heat
water
expands when it is frozen
fair test
when all the variables are held equal eg. temp, volume
reliability
repeating tests to check for variability
control
treated the same as all the samples not exposed to variables
filtration
separating out undissolved particles from a liquid
magnesium + oxygen
magnesium oxide
non metals

solid eg carbon, sulphur, iodine

liquid eg bromine

dull and brittle

most don’t conduct electricity and heat they are insulators

able to combine with oxygen to form oxides which dissolve in water to form acids

hydrogen

has physical properties of a non metal

has chemical properties of a metal has atomic number of 1

combines with oxygen to form a liquid oxide which is neutral

metals

all solid

shiny

bendy

conduct electricity and heat

can combine with oxygen to form solid oxides called bases

indicators
substances that change their colour when they come in contact with a particular substance
litmus

turns red when added to acids

turns blue when added to alkalis

does not change colour when added to neutral liquids