Practicals Flashcards

1
Q

What, in general, are irritants?

What precaution should you take when handling an irritant substance?

A

Dilute acids and alkalis

Wear goggles

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

What, in general, are corrosives?

What precaution should you take when handling a corrosive substance?

A

Stronger acids and alkalis

Wear goggles

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

What precaution should you take when handling a flammable substance?

A

Keep away from naked flames

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

What precaution should you take when handling a toxic substance?

A

Wear gloves

Avoid skin contact

Wash hands after use

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

What precaution should you take when handling a oxidising substance?

A

Keep away from flammable / easily oxidised materials

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

What 2 things could the method, heating a substance in a crucible, be used to measure?

A

This method could be used for:

  • measuring mass loss in various thermal decomposition reactions.
  • measuring mass gain when reacting magnesium in oxygen
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Describe the method of removing the water of crystallisation in calcium sulphate crystals.

Why should large amounts of calcium sulfate not be used?

Why should the cru

A

Heating in a crucible.

see page 1 in the chemrevise revision guide

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

When removing the water of crystallisation in calcium sulphate crystals through heating in a crucible:

Why should large amounts of calcium sulfate, e.g. 50g, not be used?

Why should small amounts of the solid, e.g. 0.100g, not be used?

Why should the crucible be dry?

Why do you put a lid on the crucible?

A

(see page 1 in the chemrevise revision guide)

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

Answer the example question 1 on page 1 in the chemrevise revision guide.

A

correct?

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

Draw the apparatus for when heating a substance in a crucible.

A

(see page 1 in the chemrevise revision guide)

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

What could the method, using a gas syringe, be used to measure?

A

A variety of experiments where the volume of a gas is measured.
(probably to work out moles of a gas or to follow reaction rates)

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

What 2 external variables could affect the experiment of measuring the volume of a gas in a gas syringe?

A
  • temperature
  • pressure

of the room

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

Name 3 potential errors when measuring the volume of a gas in a gas syringe.

A
  • Gas escapes before bung inserted
  • Syringe sticks
  • Some gases, e.g. CO2 or SO2, are soluble in water so the true amount of gas is not measured.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Draw the apparatus for when measuring the volume of a gas in a gas syringe.

A

(see page 2 in the chemrevise revision guide)

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

Describe the method for using a gas syringe to calculate the Mr of propanone.

A

(see page 2 in the chemrevise revision guide)

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

Answer the example question 2 on page 2 in the chemrevise revision guide.

A

correct?

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

Describe the method for making up a 250cm3 volumetric solution to carry out a simple acid-base titration.

A

(see page 3 in the chemrevise revision guide)

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

Describe the best method for measuring the mass of a substance.

A

(see page 3 in the chemrevise revision guide)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Why should you not heat or put hot solutions in a volumetric flask?

A

Because the heat would cause the flask to expand and the volume would then be incorrect.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Describe the method for how you would dilute a solution using a volumetric flask.

A

(see page 3 in the chemrevise revision guide)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Why is using a volumetric pipette more accurate than a measuring cylinder?

A

Because it has a smaller uncertainty

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Describe the general method for a simple acid-base titration.

Then give a more in-depth description of using:

The pipette
The burette
Adding the indicator

A

(see page 4 in the chemrevise revision guide)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

In a titration reaction, where does the substance we don’t know the concentration of go?

A

conical flask

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

In a titration reaction, where does the substance we do know the concentration of go?

A

burette

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Titrate solution A with solution B.

Where should you put solution A and B:

conical flask
burette

A

A - conical flask

B - burette

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

In a titration, why is a conical flask preferred over a beaker?

A

Easier to swirl the mixture without spilling the contents.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What colour is phenolphthalein in alkali?

A

pink

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What colour is phenolphthalein in acid?

A

colourless

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What colour is methyl orange in alkali?

A

yellow

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What colour is methyl orange in acid?

A

red

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

(in a titration)

If 2 or 3 values are within 1.10cm3 and therefore _______ or close then we can say results are accurate and __________ and the titration technique is good and consistent.

A

If 2 or 3 values are within 1.10cm3 and therefore concordant or close then we can say results are accurate and repeatable and the titration technique is good and consistent.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

How should you record your results from a titration?

A

(see page 6 in the chemrevise revision guide)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

In a titration, what are 4 safety precautions?

A

Acids and alkalis are corrosive, (at low concentrations acids are irritants):

  • wear eye protection and gloves.
  • Is spilled immediately wash affected parts.
  • If substance is unknown treat it as potentially toxic and wear gloves.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

Write some common titration equations.

A

(see page 6 in the chemrevise revision guide)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

In quality control why might it be necessary to do titrations/testing on several samples?

A

As the amount/concentration of the chemical being tested may vary between samples.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

When titration mixtures to work out the concentration of an active ingredient, what should you consider?

A

If the mixture contains over substances that ave acid base properties.
If they don’t have acid base properties we can titrate with confidence.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

Write the equation for the manganate redox titration with iron.

What is the colour change from reactants to products?

A

(see page 7 in the chemrevise revision guide)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

Describe the detailed procedure for finding out how much iron is in iron tablets.

A

Manganate redox titration

see page 7 in the chemrevise revision guide

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

Answer the example Q 3 on page 7 in the chemrevise revision guide.

A

correct?

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

Write the equation for the manganate redox titration with hydrogen peroxide.

A

(see page 8 in the chemrevise revision guide)

41
Q

Write the equation for the manganate redox titration with ethanedioate.

A

(see page 8 in the chemrevise revision guide)

42
Q

Answer the example Q 4 on page 8 in the chemrevise revision guide.

A

correct?

43
Q

Write the equation for the formation of EDTA through a titration.

A

(see page 8 in the chemrevise revision guide)

44
Q

Answer the example Q 5 on page 8 in the chemrevise revision guide.

A

(see page 8 in the chemrevise revision guide)

45
Q

Read box labelled 1 on page 9 in the chemrevise revision guide.

A

understand?

46
Q

Give the equation for how you would calculate % uncertainty.

A

(see page 8 in the chemrevise revision guide)

47
Q

What two things could you do to reduce uncertainties in a titration?

A
  • Replacing measuring cylinders with pipettes or burettes which have a lower apparatus uncertainty will lower the % uncertainty.
  • Larger titre volume by: increasing the volumes and concentration of the substance in the conical flask or by decreasing the concentration of the substance in the burette.
48
Q

What two things could you do to reduce uncertainties in measuring mass?

A
  • Using a balance that measures to more decimal places or using a larger mass will reduce the % uncertainty in weighing a solid.
  • Weighing a sample before and after addition and then calculating difference will ensure a more accurate measurement of the mass added.
49
Q

Answer the example question labelled 2 on page 9 in the chemrevise revision guide.

A

correct?

50
Q

Describe the general calorimetric method for measuring the enthalpy change for a reaction.

What are 5 errors of this method?

Draw the graph used in this experiment.

What equation would you use?

A

(see page 10 in the chemrevise revision guide)

51
Q

Read box labelled 1 on page 10 in the chemrevise revision guide.

A

understand?

52
Q

Answer the example Q 6 on page 11 in the chemrevise revision guide.

A

correct?

53
Q

Answer the example Q 7 on page 11 in the chemrevise revision guide.

A

correct?

54
Q

Describe the detailed method for measuring the enthalpy change of solution of anhydrous copper(II) sulphate

A

(see page 12 in the chemrevise revision guide)

55
Q

What are 6 errors in the method of measuring enthalpies of combustion using flame calorimetry?

A

(see page 13 in the chemrevise revision guide)

56
Q

Answer the example Q 8 on page 13 in the chemrevise revision guide.

A

correct?

57
Q

Describe the typical method when investigating how the rate of reaction changes with temperature using sodium thiosulfate and hydrochloric acid.

Write the equation.

A

(see page 14 in the chemrevise revision guide)

58
Q

Answer the example Q 8 on page 14 in the chemrevise revision guide.

A

correct?

59
Q

When testing for cations, describe the method of adding dilute sodium hydroxide to the solution.

What are the results for group 2?

What are the results for group 3?

A

(see page 15 in the chemrevise revision guide)

60
Q

When testing for ammonium ions, describe the method of adding dilute sodium hydroxide to the solution.

What are the results?

A

(see page 15 in the chemrevise revision guide)

61
Q

When testing for group 2 elements, describe the method of adding sulphate ions to the solution.

What are the results?

A

(see page 15 in the chemrevise revision guide)

62
Q

What is used as a reagent to test for sulphate ions?

What is the result if the test is positive?

Write the simplest ionic equation for the reaction when the test is positive.

What would be observed with a positive result?

A

BaCl2 solution acidified with hydrochloric acid

see page 16 in the chemrevise revision guide

63
Q

How do you test for the presence of halide ions?

What are the results?

A

(see page 16 in the chemrevise revision guide)

64
Q

How do you test for the presence of carbonate ions?

What is the result?

Write the equation for the reaction.

A

(see page 16 in the chemrevise revision guide)

65
Q

How do you test for hydroxide ions?

A

Alkaline hydroxide ions will turn red litmus paper blue.

66
Q

Why do halides show an increasing power as reducing agents down the group?

A

A reducing agent donates electrons.
The reducing power of the halides increases down group 7.
They have a greater tendency to donate electrons.
This is because as the ions get bigger it is easier for the outer electrons to be given away as the pull fro the nucleus on them becomes smaller.

67
Q

For when halide salts react with concentrated sulphuric acid:

Write the equation for fluorine.

What are the observations?

A

(see page 17 in the chemrevise revision guide)

68
Q

For when halide salts react with concentrated sulphuric acid:

Write the equation for chlorine.

What are the observations?

A

(see page 17 in the chemrevise revision guide)

69
Q

For when halide salts react with concentrated sulphuric acid:

Write the equation for bromine.

What are the observations?

A

(see page 17 in the chemrevise revision guide)

70
Q

For when halide salts react with concentrated sulphuric acid:

Write the equation for iodine.

What are the observations?

A

(see page 17 in the chemrevise revision guide)

71
Q

Describe the detailed method of the partial oxidation of propane-1-ol.

What are 2 safety precautions?

A

(see page 19 in the chemrevise revision guide)

  • WEAR GLOVES - solid potassium dichromate(VI) is highly toxic, category 2 carcinogen, irritant. Conc. sulfuric acid is corrosive.
  • AVOID INHALING DUST
72
Q

Describe the detailed method of the full oxidation of propan-1-ol

A

(see page 20 in the chemrevise revision guide)

73
Q

How do you test for an alkene?

A

To 0.5cm3 of bromine water in a test tube add a few drops of the unknown and shake.

Observation: alkenes should decolourise bromine water.

74
Q

How do you test for aldehydes? (2 ways)

A

(see page 22 in the chemrevise revision guide)

75
Q

How do you test for a carboxylic acid?

A

(see page 22 in the chemrevise revision guide)

76
Q

Describe the method for how you test for halogenoalkanes.

A

(see page 23 in the chemrevise revision guide)

77
Q

What two ways can initial rate be calculated experimentally?

A
  • Taking the gradient of a continuous monitoring conc v time graph at time = zero
  • Clock reactions where the time taken to react a fixed concentration is measured.
78
Q

Describe the detailed method of the common clock reaction between hydrogen peroxide and iodine.

Write the equation of the reaction.

How would you calculate rate with a graph?

A

(see page 24 in the chemrevise revision guide)

79
Q

Describe the typical method for measuring the rate of reaction with a gas syringe.

A

(see page 25 in the chemrevise revision guide)

80
Q

Name 6 ways in which rate of reaction can be measured.

A
  • Measurement of the change in volume of gas
  • Measurement of change of mass
  • Titrating samples of reaction mixture with acid, alkali. sodium thiosulfate etc.
  • Colorimetry
  • Measuring change in electrical conductivity.
  • Measurement of optical activity.

(see page 26 in the chemrevise revision guide)

81
Q

Describe the method of measuring the EMF of an electrochemical cell.

What does the salt bridge do?

A

(see page 27 in the chemrevise revision guide)

82
Q

Describe the method of measuring the EMF of an electrochemical cell if one or both of the half cells do not contain a conducting metal.

A

(see page 27 in the chemrevise revision guide)

83
Q

Describe the method for constructing a pH curve through a titration.

A

(see page 28 in the chemrevise revision guide)

84
Q

Describe the detailed method for the preparation of aspirin.

Write the equation.

A

(see page 30 in the chemrevise revision guide)

85
Q

Read the box labelled 1 on page 30 in the chemrevise revision guide.

A

understand?

86
Q

Describe one way in which you can measure melting point of a substance.

A

(see page 31 in the chemrevise revision guide)

87
Q

Describe the general method for the preparation of an organic liquid.

A

(see page 32 in the chemrevise revision guide)

88
Q

Describe the detailed method for preparing and purifying cyclohexane from cyclohexanol.

A

(see page 32 in the chemrevise revision guide)

89
Q

Describe the detailed method for preparing and purifying an ester.

A

(see page 33 in the chemrevise revision guide)

90
Q

When testing aqueous transition metal ions:

Describe the method of adding sodium hydroxide.

What is the reaction with limited OH- ions?

What is the reaction with excess OH- ions?

A

(see page 34 in the chemrevise revision guide)

91
Q

When testing aqueous transition metal ions:

Describe the method of adding ammonia solution.

What is the reaction with limited NH3?

What is the reaction with excess NH3?

A

(see page 34 in the chemrevise revision guide)

92
Q

When testing aqueous transition metal ions:

Describe the method of adding sodium carbonate.

What is the reaction?

A

(see page 34 in the chemrevise revision guide)

93
Q

Describe the method for separating species by thin-layer chromatography.

A

(see page 35 in the chemrevise revision guide)

94
Q

Describe the method for an experiment used to calculate the equilibrium constant Kc.

A

(see page 36 in the chemrevise revision guide)

95
Q

Answer the example question labelled 1 on page 36 in the chemrevise revision guide.

Answer the example question labelled 2 on page 37 in the chemrevise revision guide.

Answer the example question labelled 3 on page 37 in the chemrevise revision guide.

A

correct?

96
Q

Describe the detailed method of measuring the absorption of copper solutions.

A

(see page 38 in the chemrevise revision guide)

97
Q

Describe the general method for determining the concentration of coloured ions.

A

(see page 38 in the chemrevise revision guide)

98
Q

How does spectrophotometry work?

A

(see page 38 in the chemrevise revision guide)

99
Q

Describe the detailed method of the rate of the autocatalytic reaction between ethanedioate and manganate ions.

Write the equation.

Explain the observed results.

A

(see page 39 in the chemrevise revision guide)