Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Chemistry > C4 > Flashcards

C4 Flashcards

1
Q

Metal + oxygen is what and what reaction takes place?

A

Metal oxide, oxidation reaction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What happens in an oxidation reaction?

A

Oxygen is gained and electrons are lost.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What happens in a reduction reaction?

A

Oxygen is lost and electrons are gained.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

G1 metal + water is what

A

Metal hydroxide (alkali) + hydrogen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What metals do not react with water at room temperature?

A

Magnesium, zinc, iron, copper

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What metals react rapidly and quite rapidly with water at room temperature?

A

Potassium, sodium, lithium and (calcium reacts quite rapidly).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What does the reactivity of a metal depend on?

A

Its ability to lose electrons and from a positive ion.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Half equation for oxidation for magnesium

A

Mg -> Mg2+ + 2e-

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Half equation for reduction for sulfur

A

S + 2e- -> S2-

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What ions do acids produce in aqueous solutions?

A

Hydrogen ions (H+)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Acid + base is what and what type of reaction is it?

A

Salt + water, neutralisation reaction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are bases usually?

A

Metal oxides or metal hydroxides

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Define alkali

A

A base that is soluble in water.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What ions do alkalis produce in aqueous solutions?

A

Hydroxide ions (OH-)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

H+ + OH- is what

A

H2O - water

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Metal + water is what and what reaction is it?

A

Salt + hydrogen, displacement reaction (metal has displaced the hydrogen)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

In a metal + acid reaction, what is oxidised and what is reduced?

A

Metals are oxidised and acid is reduced

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Define base

A

Chemicals which can neutralise acids and produce a salt and water.

19
Q

Acid + metal carbonate is what?

A

Salt + water + carbon dioxide

20
Q

How to make soluble salts (practical)?

A
  1. Warm the dilute acid using a Bunsen burner, then turn it off.
  2. Add the insoluble base to the acid a bit at a time, until no more reacts (the base is in excess).
    The acid will be neutralised when the excess solid will just sink to the bottom of the flask.
  3. Filter out the excess solid to get the salt solution.
  4. To get pure, solid crystals of the salt, leave the solution for 24 hours in a cool place.
    Crystals should form, which can be filtered out the solution and then dried using a paper towel - crystallisation.
21
Q

What happens to acid molecules in solution?

A

Acid molecules ionise (split) and release H+.

22
Q

How do strong acids ionise in aqeous solutions?

A

Fully ionise is aqueous solutions.

23
Q

3 strong acids

A

Hydrochloric / sulfuric / nitric acid

24
Q

How do weak acids ionise in aqeous solutions?

A

Partially ionise in aqueous solutions (reversible reaction).

25
Q

3 weak acids

A

Carbonic / ethanoic / citric acid

26
Q

Why do strong acids have a lower pH than weak acids?

A

Strong acids fully ionise creating a greater concentration of hydrogen ions than weak acids.

27
Q

How many times greater is the concentration of H+ in pH 1 than 2?

A

10x greater (one order of magnitude)

28
Q

Define the concentration of an acid

A

The amount of acid molecules in a given volume of solution. A dilute acid will have fewer acid molecules in a given volume than a concentrated acid even if the strength is the same.

29
Q

How to make an ionic compound conduct electricity?

A

Melt it or dissolve in water - the forces of attraction are broken and ions are free to move.

30
Q

What is the negative and positive electrode called and what are they covered with?

A

Cathode - colvered with electrons, anode - lack of electrons

31
Q

Which electrode are the positive ions attracted to what reaction is it?

A

The negative electrode - cathode, reduction reaction.

32
Q

Which electrode are the negative ions attracted to what reaction is it?

A

The positive electrode - anode, oxidation reaction.

33
Q

Metals that are more reactive than carbon are extracted using what?

A

Electrolysis

34
Q

Metals that are less reactive than carbon are extracted using what?

A

Carbon

35
Q

How is electrolysis of aluminium oxide done?

A
  1. Aluminium oxide is mixed with cryolite with lowers the melting point - reduces the amount of energy needed and saves money. 2. The cathode attracts the positive aluminium ions and the negative oxide ions attracts to the anode.
36
Q

Why must the anode be replaced regularly?

A

The oxygen molecules produced at the anode reach with the graphite (carbon), forming carbon dioxide gas. C + O2 -> CO2

37
Q

Why is electrolysis expensive?

A

Melting the compounds requires a great deal of energy and a lot of energy is required to produce the electric current.

38
Q

In the electrolysis of aqueous solutions, what is produced at the cathode if the metal is more reactive then hydrogen? What is the half equation?

A

Hydrogen, 2H+ + 2e- -> H2

39
Q

In the electrolysis of aqueous solutions, what is produced at the cathode if the metal is less reactive then hydrogen? What is the half equation?

A

Pure metal, Cu2+ + 2e- -> Cu

40
Q

In the electrolysis of aqueous solutions, what is produced at the anode if a halide ion is present? What is the half equation?

A

Halogen gas, Cl- -> Cl2 + 2e-

41
Q

In the electrolysis of aqueous solutions, what is produced at the anode if a halide ion is not present? What is the half equation?

A

Oxygen, 4OH- - 4E- -> 2H2O + O2

42
Q

Test for chlorine gas

A

Bleaches damp blue litmus paper

43
Q

Test for hydrogen gas

A

Produces a squeaky pop near a lit splint

44
Q

Metal + acid is what

A

Salt and hydrogen

Chemistry (5 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions