GCSE Chemistry Organic families questions by topic

(Chemistry only) This question is about alcohols.

1. (a)Give the formula of ethanol.[1]
2. (b)Name the functional group shared by all alcohols.[1]
3. (c)Name the products when ethanol burns completely in oxygen.[1]

(Chemistry only) Yeast, water and glucose are mixed in a warm vessel sealed from the air.

1. (a)Name the process happening.[1]
2. (b)Write the word equation for the reaction.[2]
3. (c)State why the vessel is sealed from the air.[1]

(Chemistry only) Ethene, C₂H₄, reacts with steam to make ethanol.

1. (a)Write the balanced equation.[2]
2. (b)State the raw material that ethene is cracked from.[1]

(Chemistry only) Vinegar contains ethanoic acid.

1. (a)Give the formula of ethanoic acid.[1]
2. (b)State the pH expected for a dilute solution of ethanoic acid.[1]
3. (c)Describe what is observed when ethanoic acid is added to sodium hydrogencarbonate.[2]

Complete the sentences and table about alcohols.

1. (a)Complete the formula of ethanol.[1]
2. (b)Complete the formula of propan-1-ol.[1]
3. (c)State the functional group carried by every alcohol.[1]
4. (d)Name the process that makes ethanol from glucose.[1]
5. (e)State what ethanol forms when it is oxidised.[1]

Vinegar is a solution of ethanoic acid. Two solutions of the same concentration, one of ethanoic acid and one of hydrochloric acid, are tested with a pH meter: the vinegar reads pH 2.9, the hydrochloric acid pH 1.0.

1. (a)State which acid is stronger and explain why the two pH values differ.[2]
2. (b)Write the word equation for neutralising ethanoic acid with sodium hydroxide solution.[2]
3. (c)State the observation when ethanoic acid reacts with sodium hydrogencarbonate.[1]

(Chemistry only) A chemical plant and a farm both make ethanol.

1. (a)Write the equation for each route.[2]
2. (b)Give one advantage and one disadvantage of the farm route.[2]
3. (c)State why the plant route depends on a finite resource.[2]

(Chemistry only) Ethanol is oxidised in the lab using acidified potassium manganate(VII).

1. (a)Name the organic product.[1]
2. (b)Write the equation using [O] to represent the oxidising agent.[2]
3. (c)Name the acid produced when wine is left open to air, and the process causing it.[2]

Ethene, CH₂=CH₂, is polymerised to make poly(ethene).

1. (a)Describe what happens to the double bond during polymerisation.[2]
2. (b)State the other product formed, if any.[1]
3. (c)Describe how to draw the repeat unit.[2]

(Chemistry only) Two dilute acids, hydrochloric and ethanoic, have the same concentration.

1. (a)Explain the difference between a strong and a weak acid.[2]
2. (b)Predict and explain which acid gives the faster reaction with magnesium ribbon.[3]
3. (c)State which acid has the higher pH.[1]

Ethene molecules are polymerised industrially to make poly(ethene).

1. (a)Describe what happens to the double bond when ethene molecules join into the polymer.[2]
2. (b)Sketch or describe the repeat unit of poly(ethene).[2]
3. (c)State the difference between the repeat units of poly(ethene) and poly(chloroethene), and explain where the difference comes from.[2]

A class makes an ester by warming ethanoic acid with ethanol in the presence of a few drops of concentrated sulfuric acid.

1. (a)Write the word equation for the reaction.[2]
2. (b)Name the ester formed.[1]
3. (c)State the role of the sulfuric acid.[1]
4. (d)Describe how the class would know the reaction worked, and give one everyday product where esters matter.[2]

(Higher) Polymer A has long straight chains that pack closely. Polymer B has the same monomer but its chains are heavily branched.

1. (a)Compare the bonding within a chain and between chains.[2]
2. (b)Predict which polymer melts at the higher temperature and explain why.[3]
3. (c)Predict which is more flexible and explain your choice.[2]

(Chemistry only) Ethane-1,2-diol (a diol) reacts with a dicarboxylic acid to form a polyester.

1. (a)Name the small molecule released at each new link.[1]
2. (b)Explain why each monomer needs two functional groups.[3]
3. (c)State one property that makes polyesters useful for drinks bottles.[2]

(Higher, Chemistry only) Compare addition and condensation polymerisation.

1. (a)State the monomer type and other product for each process.[4]
2. (b)Explain what happens to the bonds in addition polymerisation.[1]
3. (c)Name the polymer family made from amino acids, and the link formed.[2]

(Chemistry only) This question is about DNA.

1. (a)Name the monomer that polymerises into each DNA strand.[1]
2. (b)Describe the overall structure of DNA.[3]
3. (c)Explain the role of the base pairs.[2]

Polyesters such as PET (used for drink bottles and fibres) are made from a dicarboxylic acid and a diol — molecules with two carboxylic acid groups and two alcohol groups respectively.

1. (a)Explain why each monomer needs two reactive groups for condensation polymerisation.[2]
2. (b)Name the linkage that forms between the monomers and the small molecule lost.[2]
3. (c)State two differences between condensation and addition polymerisation.[2]
4. (d)State why PET can be recycled by melting, unlike thermosetting polymers.[1]

This question is about the polymers of life: proteins and DNA.

1. (a)Name the two functional groups carried by every amino acid.[2]
2. (b)Describe how amino acid molecules join to form a protein chain.[2]
3. (c)Describe the structure of a DNA molecule.[3]
4. (d)Name the monomers of DNA.[1]