Organic Chemistry (OCR Gateway GCSE Chemistry: Combined Science)

The complete combustion of pentane, C₅H₁₂, takes place in the following unbalanced equation:

_C₅H₁₂   +   _O₂ →   _CO₂   +  _H₂O

What numbers will balance the reaction?

Which of the following molecules is an alkene?

Which molecule can be cracked to produce hexane, C₆H₁₄?

Which of the following shows the product of the reaction between propene and bromine?

Crude oil is a mixture of hydrocarbons.

Crude oil is separated into useful fractions.

Which of these mixtures of substances could be in a fraction from crude oil?

Crude oil is separated into useful fractions by fractional distillation.

The diagram shows the useful fractions made in fractional distillation.

Which of these fractions has the weakest intermolecular forces?

Crude oil is separated into fractions by fractional distillation.

Look at the diagram of the fractions made in fractional distillation.

Which of these fractions has the lowest boiling point?

What type of reaction takes place between an alkene and hydrogen?

Ethene, C₂H₄, reacts with bromine, Br₂, in an addition reaction.

Which is the balanced symbol equation for this reaction?

The bar chart shows the amount of some fractions made from 100 tonnes of crude oil by fractional distillation.

It also shows the amount of each fraction needed for everyday uses.

Cracking converts large molecules into smaller more useful molecules to make the supply match the demand.

Which fractions are most likely to be cracked to make the supply match the demand?

What is the formula of the product in this equation?

What is the general formula of the fractions produced by the fractional distillation of crude oil?

A student reacts a hydrocarbon with bromine water.

The formula of the product is C₃H₆Br₂.

Which is the displayed formula of the hydrocarbon?

A student bubbles ethene gas into bromine water.

Which displayed formula shows the product of this reaction?