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How do group one metals react in water?
they react vigorously
They produce a metal hydroxide solution
Produces hydrogen - fizzing
What is the word equation for sodium (group 1) and water
Sodium + water → sodium hydroxide + hydrogen
What happens to group 1 metals when left in air?
they react with oxygen, forming oxides
they tarnish, leaving a dull metal oxide layer.
What is the word equation for alkali metals in water?
Metal + water → metal hydroxide + hydrogen
What is the reactivity trend in group 1?
As you go down, the elements become more reactive.
Where can the group 1 metals trend in reactivity be seen?
rate of reaction with water to react completely with the water and disappear
Rate of reaction with oxygen to react and form its oxide
Why does group one reactivity happen?
all group one metals have one electron in their outer shell
As you go down group one, the atoms get bigger, the outer shell distance from nucleus increase
The attraction between the outermost electron an the nucleus becomes less, the outer electron is more easily lost and therefore more reactive
What is chlorine at room temperature?
fairly reactive
Poisonous
Green gas
What is bromine at room temperature?
poisonous
Red-brown liquid which gives off orange vapour
What is iodine at room temperature?
dark grey crystalline solid
Gives off purple vapour when heated
What is the trend of boiling point and colour of halogens?
as the atomic number increases, the elements get darker and have higher boiling point.
what is the reactivity trend of halogens?
the reactivity decreases going down group 7
why does the reactivity trend happen in group 7 metals?
halogens have seven electrons in their outer shell.
the more shells there are, the harder it is to attract the extra electron to fill the outer shell when its further away from the nucleus
the atoms with less shells are therefore more reactive as they can easily attract the extra electron.
what happens when two halogens react with eachother?
the more reactive halogen will displace the less reactive reactive one. a colour change will occur
what happens during displacement reactions?
displacement reactions are redox reactions.
an electron will be passed from the less reactive halogen to the more reactive halogen.
what is the proportions of gases in the atmosphere?
78% nitrogen
21% oxygen
1% argon
0.04% carbon dioxide
what does iron do to air?
it reacts with oxygen in the air, to form rust, therefore removing oxygen from the air.
how to investigate the proportion of oxygen in the air using iron?
soak iron wool in acetic acid, then push the wool into a measuring cylinder
invert the measuring cylinder into a beaker of water and record the starting position of the water (starting volume of air)
over time the level of water in the cylinder will rise
this is because the iron reacts with the oxygen to make iron oxide
leave the measuring cylinder for a week or until the water level stops changing
record the finishing position of the water
how to investigate the proportion of oxygen in the air using phosphorus?
place the phosphorus in a tube and attach glass syringes at either end
make sure one is filled with air and the other is empty
measure the starting amount of air
heat the phosphorus and use the syringes to pass the air over it
the phosphorus will react with oxygen to make phosphorus oxide
as it reacts, the volume of air will decrease.
measure the final volume of air.
what is the formula for calculating the percentage of oxygen in the atmosphere?
(start volume - final volume) / start volume x 100
what happens when magnesium combusts?
bright white flame
forms magnesium oxide (white powder, slightly alkaline when dissolved in water)
what happens when hydrogen combusts?
pale blue flame
forms water (as water vapour)
what happens when sulfur combusts?
pale blue flame
produces sulfur dioxide (acidic when dissolved in water)
what happens when you heat a metal carbonate?
thermal decomposition
carbon dioxide and metal oxide formed
what happens when copper carbonate is thermally decomposed?
CuCO3 → CuO + CO2
you can test the gas thats given off for CO2
what are the greenhouse gases?
CO2, CH4, water vapour
what do greenhouse gases do?
they naturally act like an insulating layer, absorbing heat that would be radiated out into space, re-radiating it back to earth.
how does human activity effect the amount of CO2?
deforestation means less CO2 is removed from the atmosphere via photosynthesis
burning fossil fuels means carbon that was “locked up” in these fuels is released as CO2.
increasing amounts of CO2 affects climate change, increasing temperature.
balanced symbol equation for combustion of magnesium
2Mg + O2 → 2MgO
balanced symbol equation for combustion of hydrogen
2H2+ O2 → 2H2O
balanced symbol equation for combustion of sulfur
S + O2 → SO2
Equation for acid + metal
Acid + metal → salt + hydrogen
Mneumonic for reactivity series
Please stop lying cause my African zebra is cunty slay girl
Reactivity series
Potassium Sodium Lithium Calcium Magnesium Aluminium Zinc Iron Copper Silver Gold
Describe the test for measuring rate of reaction between HCl/HSO4 and metals
Setup 3 boiling tubes and fill them with equal volumes of dilute HCl or HSO4
Then place equal sizes of magnesium, zinc and iron into diff test tube
The speed of the reaction is indicated by the rate at which the bubbles of hydrogen occur
You can test for hydrogen by using squeaky pop test
How doe magnesium react with cold dilute acids
vigorously
Produces lots of bubbles
How do zinc and iron react with dilute acids
slowly
More strong if heated
Equation for metal + water
Metal + water → metal hydroxide + hydrogen
What metals react with water
very reactive metals
Potassium, sodium, lithium, calcium
What metals react with steam
less reactive metals that wont react with cold water
Magnesium, zinc, iron
How do potassium, sodium, lithium and calcium react with water?
Metal + water → metal hydroxide + hydrogen
vigorously
Produces bubbles of hydrogen gas, which can be tested
How do magnesium, zinc, iron react with steam?
metal + steam → metal oxide + hydrogen
Soak mineral wool with water, heat it in test tube
The steam given off will react with metal in a test tube
The gas given off will then burn when lit with a burning splint
What happens when two metal react
the more reactive metal will displace the less reactive one
Displacement reaction - redox reactions
What happens when a metal oxide and metal reacts
the more reactive metal will displace the less reactive metal from its oxide as it will bond more strongly to the oxygen
The metal is oxidised and the displaced metal ion is reduced
What happens when a reactive metal is placed into a solution of a less reactive metal salt
the reactive metal will displace the less reactive metal
If a reaction has occurred, the temperature will change
A more reactive metal will give a greater temperature change than a less reactive metal
In what conditions does iron rust?
when the iron is in contact with both oxygen and water
What is the word equation for rusting of iron?
Iron + oxygen + water → hydrated iron(III) oxide
How to prevent rusting
barrier methods: painting/casing it with plastic or oiling/greasing it
Galvanisation: coating it with zinc, as it is more reactive than iron, so it will be oxidised instead
Sacrificial protection: placing a more reactive metal with the iron - the water and oxygen react with the metal instead of the iron
What is the oxidising agent?
The substance that is reduced
What is the reducing agent?
The substance that is oxidised
Note 
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