Past Paper Foundation 2 Flashcards
(20 cards)
Best way to separate ethanol from water?
Fractional Distillation
Best way to separate Salt from sea water?
Crystallisation
What happens in simple distillation?
The mixture is heated to make the liquid evaporate
then the vapour is cooled to make it condense
Why is a mixture of metals harder than pure ones?
The layers in the mixture are distorted, making them harder to slide over eachother
What is the structure of hydrogen bromide?
Small Covalent
What is the formula for Fluorine gas?
F2
What did James Chadwick prove the existence of?
Proton
Explain how the reactivity of the halogens changes going down Group 7.
the reactivity decreases (going
down Group 7)
(because) chlorine displaces
bromine and iodine
(
and) bromine displaces iodine
or iodine does not react
Why can Graphite conduct electricity?
Because it has delocalised electrons
Electrolysis
* molten zinc chloride
* potassium bromide solution.
What are the products?
cathode anode
zinc (1) chlorine (1)
hydrogen (1) bromine (1)
If the metal in the compound is more reactive than hydrogen
then hydrogen gas will be produced.
If the metal is less reactive than hydrogen,
then the metal itself will be produced.
Rule: If the metal in the compound is more reactive than hydrogen, then hydrogen gas will be produced. If the metal is less reactive than hydrogen, then the metal itself will be produced.
Why?
The less reactive element is easier to “reduce” (gain electrons). So, if hydrogen is less reactive than the metal ion present, hydrogen will be formed.
If halide ions are present at electrolysis
then the halogen (chlorine, bromine, or iodine) will be produced.
If halide ions
are present, then the halogen (chlorine, bromine, or iodine) will be produced.
Why?
Halide ions are usually easier to “oxidise” (lose electrons) than the hydroxide ions (OH
−
) from water.
If no halide ions are present:
If there are no halide ions (e.g., if you have a sulfate, nitrate, or carbonate solution), then oxygen gas (O
2
) will be produced from the oxidation of the hydroxide ions in water
A student investigated the mass of copper oxide produced by heating
copper carbonate.
This is the method used.
1. Weigh an empty test tube.
2. Weigh 2.00 g of copper carbonate into the test tube.
3. Heat the copper carbonate until there appears to be no further change.
4. Re-weigh the test tube and copper oxide produced.
5. Subtract the mass of the empty tube to find the mass of copper oxide.
6. Repeat steps 1–5 twice.
7. Repeat steps 1–6 with different masses of copper carbonate.
Suggest how the investigation could be improved to make sure the reaction
is complete.
reheat
(and reweigh) until constant
mass
All alkalis contain the same ion.
What is the formula of this ion?
OH–
Soluble salts box are formed by reacting metal oxides with acids.
Give one other type of substance that can react with an acid to form a soluble salt.
- metal
- (metal) hydroxide
- (metal) carbonate
- alkali
Iron is a transition metal.
Sodium is a Group 1 metal.
Give two differences between the properties of iron and sodium.
iron has a high(er) melting /
boiling point
* iron is dense(r)
* iron is hard(er)
* iron is strong(er)
* iron is less reactive
