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Pearson Edexcel International GCSE (9–1) · CHEMISTRY · Unit

Organic Chemistry

785 practice questions

Start practising (335 questions)

Topics covered

Practice questions

201–210 of 335 · Normal

  1. Question 201

    4 marks · Normal

    (a)

    What is the appearance of the potassium dichromate(VI) solution before ethanol is added?

    [1 mark]
    (b)

    Describe the appearance of the solution after heating with ethanol.

    [2 marks]
    (c)

    What does the observed colour change indicate about the reaction?

    [1 mark]
    Answer and see the solution →

  2. Question 202

    2 marks · Normal

    Describe what happens to ethanol when it is heated with potassium dichromate(VI) in dilute sulfuric acid. Include what is formed in the reaction.

    Answer and see the solution →

  3. Question 203

    4 marks · Normal

    (a)

    State the initial colour of potassium dichromate(VI) solution before ethanol is added and heated.

    [1 mark]
    (b)

    Describe the colour change observed when ethanol is oxidised by heating with potassium dichromate(VI) in dilute sulfuric acid.

    [2 marks]
    (c)

    Name the ion that causes the final colour observed.

    [1 mark]
    Answer and see the solution →

  4. Question 204

    3 marks · Normal

    A student plans to oxidise ethanol using potassium dichromate(VI) in dilute sulfuric acid. Explain, with reasoning, the role of the sulfuric acid in this reaction and what would happen if it was not included.

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  5. Question 205

    2 marks · Normal

    State two conditions required for the fermentation of glucose to produce ethanol.

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  6. Question 206

    4 marks · Normal

    (a)

    Describe how ethanol can be made by fermentation of glucose.

    [2 marks]
    (b)

    State the main product formed if the fermentation is carried out in the presence of air.

    [1 mark]
    (c)

    Explain why the fermentation reaction is slow if the temperature is below 30°C.

    [1 mark]
    Answer and see the solution →

  7. Question 207

    3 marks · Normal

    In a fermentation process, 180 g of glucose is completely converted to ethanol and carbon dioxide.

    Calculate the mass of ethanol produced.

    The equation for fermentation is:

    M_r values: glucose (C6H12O6) = 180, ethanol (C2H5OH) = 46

    Answer and see the solution →

  8. Question 208

    3 marks · Normal

    Ethanol can be produced by fermentation or by the hydration of ethene.

    Explain two advantages and one disadvantage of making ethanol by fermentation instead of from ethene.

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  9. Question 209

    4 marks · Normal

    (a)
    Data: Rate of ethanol production at different temperatures
    Temperature (°C)Ethanol produced after 2 days (cm³)
    103
    2015
    3028
    4010
    500

    Describe the effect of temperature on the amount of ethanol produced after 2 days.

    [2 marks]
    (b)

    Suggest a temperature range suitable for the fermentation process to produce the most ethanol.

    [1 mark]
    (c)

    Explain why no ethanol is produced at 50°C.

    [1 mark]
    Answer and see the solution →

  10. Question 210

    1 mark · Normal

    Which statement about fermentation in ethanol production is correct?

    1. A.Yeast converts glucose to ethanol only at temperatures above 50°C.
    2. B.Fermentation must be carried out in the presence of air.
    3. C.Ethanol is produced by yeast enzymes acting on sugars.
    4. D.Water and carbon dioxide are the only products.
    Answer and check →