inorganic chemistry Flashcards
how do group one metals react with water (Li, Na, K)
vigorously
produce hydrogen
form metal hydroxide solution (alkaline)
metal +water -> metal hydroxide + hydrogen
how do group one metals react with oxygen in air (Li, Na, K)
form metal oxides
this is why they tarnish when left in air (form layer of metal oxide)
explain the trend in reactivity in group 1
gets more reactive as you go down because:
1) the distance from the nucleus (where the positive charge is) and the outermost electron increases
2) there is more shielding
3) both these things outweigh the increase in the number of protons in the nucleus
therefore it is easier to lose the outermost electron
describe the trend in physical properties of group 7 elements
as you go down they get darker and have higher boiling points (so at top light gases and at bottom dark solids)
what colour and state is Cl at room temperature
green gas (poisonous)
what colour and state is Br at room temperature
red-brown liquid, gives off orange vapour at room temp (poisonous)
what colour and state is l at room temperature
dark grey crystalline solid, gives of purple vapour when heated
explain the chemical trends in group 7 elements
as you go down, they get less reactive because:
1) the atomic radius increases
2) there is greater shielding
3) both these things outweigh the increase in the number of protons in the nucleus
therefore it is harder to attract an electron
describe displacement reactions with halogens
more reactive halogens displace less reactive ones from a compound
what makes up air
78% nitrogen
21% oxygen
1% argon
0.04% co2
decsribe the thermal decompostion of metal carbonates
metal carbonate -> metal oxide + carbon dioxide
eg: copper carbonate (green powder) -> copper oxide (black) + co2
list the reactivity series
K Na Li Ca Mg Al Zn Fe Cu Ag Au
what is the reaction of metals with acids
acid +metal -> salt + hydrogen
what is the reaction of metals with water
reactive metals: metal+ water-> metal hydroxide+ hydrogen
less reactive: metal + steam -> metal oxide + hydrogen
what is the word equation for rusting
iron +water-> hydrated iron(iii)oxide (rust)
what is oxidation
the loss of electrons or gain of oxygen
what is reduction
the gain of electrons or loss of oxygen
what is a redox reaction
where reduction and oxidation happen simultaneosly
what is an oxidising agent
accepts the electron; gets reduced
what is a reducing agent
donates the electron; gets oxidised
what colour is litmus in acid/alkali
red= acid; purple=neutral; blue= alkali
what colour is phenolphthalein in acid/alkali
colourless= acid; pink= alkali
what colour is methyl orange in acid/alkali
red= acid; yellow= alkali
what is an acid
a source of H+ IONS (proton donors)
what is an alkali
a soluble base; source of OH- ions ( proton acceptors)
which ions make soluble ionic compounds
sodium, potassium, ammonium
are nitrates soluble
yes
are cholrides soluble
yes, except silver and lead ii
are sulfates soluble
yes, except barium, calcium, lead
are carbonates soluble
no, except na, k, nh4
are hydroxides soluble
no, except na, k, nh4 (and Ca(OH)2 IS SLIGHTLY soluble)
make a soluble salt
react an acid with an insoluble base heat acid in water bath add base stop adding when solid stays at bottom filter out excess solid heat gently then leave to crystalise
test for oxygen
relights glowing splint
test for H
makes a squeaky pop with a lit splint
test for co2
turns limewater cloudy
ammonia test
turns damp red litmus paper blue + smells
Test for chlorine
bleaches damp blue litmus paper (turns white)
flame test for Li+
red
flame test for Na+
yellow
flame test for K+
lilac
flame test for Ca2+
orange-red
flame test for Cu2+
blue green
test for NH4+
add sodium hydroxide then test for ammonia gas (damp red litmus goes blue)
test for Cu2+
add sodium hydroxide and BLUE PRECIPITATE forms
test for Fe2+
add sodium hydroxide and SLUDGY GREEN PRECIPITATE forms
test for Fe3+
add sodium hydroxide and RED/BROWN PRECIPITATE forms
test for Cl-
add dilute nitric acid then silver nitrate solution: white precipitate
test for Br-
add dilute nitric acid then silver nitrate solution: cream precipitate
test for I-
add dilute nitric acid then silver nitrate solution: yellow precipitate
test for water
anhydrous copper sulfate = white; hydrated copper sulfate= blue
test for pure water
boils at 100 degrees celcius
Describe how to carry out an acid alkali titration ( with known volume of acid)
Using a Pipette and Pipette filler, add 25 cm3 of alkali to a conical flask with some indicator
Fill a burette with the acid
Add the acid to the alkali slowly, swirling it regularly
When the colour changes record the volume
Repeat until you get the same result
How to make an insoluble salt
Pick two soluble salts
Eg to make lead Sulfate, use lead nitrate and magnesium Sulfate
Dissolve equal amounts of each salt in pure water
Mix the two solutions and stir
Filter out the precipitate
Wash and dry
How to make a soluble salt using titration
Using a Pipette and Pipette filler, add 25 cm3 of alkali to a conical flask with some indicator
Fill a burette with the acid
Add the acid to the alkali slowly, swirling it regularly
When the colour changes record the volume
Repeat without the indicator
Evaporate off some of the water
Leave to crystallise
Filter off the solid
Dry it
How to make a soluble salt (not titration)
Use acid + insoluble base
Heat the acid in a water bath (in a fume cupboard)
Add the base to the acid until in excess (when solid is left)
Filter off the excess solid
Heat solution gently
Leave to cool and crystallise
Filter and dry
What colour flame does sulfur burn with
Blue
What happens to HCL in water
Disassociates into H+ ions and CL- ions
Litmus turns red
What happens to HCL in methylbenzene
Doesn’t disassociate
Litmus stays blue
Name an iron ore
Haematite
Magnetite
How does limestone remove the impurity silica from a furnace
Limestone (calcium carbonate) decomposes to form CaO
CaO reacts with silica to form calcium silicate
Describe how aluminium is extracted from purified aluminium oxide
Aluminium is extracted by electrolysis Aluminium added to cryolite Electrolyte molten Carbon/graphite electrodes used Aluminium ions discharged/ aluminium formed at cathode
