inorganic Flashcards
why does reactivity decrease as you move down group 1 of the periodic table
the atomic radius increases so the outer electron is more easily lost due to a weaker force of attraction
what does chlorine look like
green gas and toxic/poisonous
what does bromine look like
brown liquid
what does iodine look like
grey solid
why does reactivity decrease down the group
because atomic radius gets smaller, so greater forces of attractions require to remove outer electron
how can you find the percentage of oxygen in air
place some steel wool in a tube
invert the tube and place in water
measure height of air in the tube
iron reacts with water causing water to move up the tube
after 7 days, record the new height of air in the tube
how can phosphorous be used to measure oxygen percentage
place phosphorous in a tube and connect either ends to 2 gas syringes
push air across phosphorous while heating
when volume of air remains constant, all oxygen has reacted
allow cooling
how does magnesium burn in air
white flame
how does hydrogen burn in air
squeaky pop with red flame
how does sulphur burn in air
blue flame
what is thermal decomposition
the breaking down of chemicals into smaller parts through the use of heating
what colour will litmus paper go in acid
will turn red due to presence of hydrogen ions
what colour will phenolphthalein go in alkaline
pink
what colour will methyl orange go in acid
orange ( it will go yellow in alkaline)
what is an acid
solution that neutralises a base, has a pH under 7, and reacts to produce hydrogen ions, proton donors
what is a base
solution that neutralises an acid, has a pH over 7, and reacts to produce hydroxide ions, proton acceptors
which chlorides are insoluble
silver and lead (II)
which sulphates are insoluble
barium, calcium, and lead (II)
which carbonates and hydroxides are soluble
sodium, potassium, ammonium
how can you produce a soluble salt using an insoluble base
using sulphuric acid and copper (II) oxide
warm a solution of dilute sulphuric acid
add some copper (II) oxide until sulphuric acid stops dissolving
blue copper sulphate produced and copper (II) oxide solid
filter the solution, and allow it to cool, causing the solution to crystalise following evaporation
how can you test for the following: hydrogen
oxygen
carbon dioxide
ammonia
chlorine
burns with squeaky pop
relights a glowing splint
limewater cloudy
turns damp red litmus paper blue
bleaches litmus paper
how do the following cations burn: lithium
sodium
potassium
calcium
copper
red
yellow
lilac
orange
green
how can you test for the ammonium ion
add sodium hydroxide and warm the solution
if ammonium is present, damp red litmus paper will turn blue
strong smell is given off
what colour are the precipitates of the following: copper
iron
iron(III)
blue
green
brown
what colour are the precipitates of halides with silver nitrate + nitric acid
chloride - white
bromide - cream
iodide - yellow
how do you test for the sulphate ion
sulphate ions produce a white precipitate when they react with barium chloride + HCL
how can you test for water using hydrated copper sulphate crystals
heat blue hydrated copper sulphate crystals
a white powder is left behind
add water to the solution
the crystals will return
water is pure if it boils at 100 degrees Celsius
if it freezes at 0 degrees Celsius
what is a displacement reaction
where a more reactive metal displaces a less reactive metal
what is redox
a reaction involving both oxidisation and reduction
what is rusting
the corrosion of iron
hydrated iron oxide
how do barrier methods work
painting/coating with plastic
oiling or greasing
how does sacrificial protection work
more reactive metal coated over the iron e.g. zinc, which will be oxidised instead, this method is known as galvanising
