The alkanes are a homologous series of hydrocarbons obtained from the fractions of crude oil.
Describe how crude oil is separated into fractions in industry.
State the general formula of the alkanes.
State two characteristics, other than having the same general formula, of members of a homologous series.
Butane is an alkane used as a fuel. Balance the equation for the complete combustion of butane:
C4H10+…O2→…CO2+…H2O \text{C}_4\text{H}_{10} + \dots \text{O}_2 \rightarrow \dots \text{CO}_2 + \dots \text{H}_2\text{O} C4H10+…O2→…CO2+…H2OIncomplete combustion of butane leads to the formation of a poisonous gas. Identify this gas.
Explain why the gas is poisonous.
During the combustion of butane at high temperatures, gases represented by the formula NOx\text{NO}_xNOx can form. Which two elements combine to form these gases?
The alkane C5H12\text{C}_5\text{H}_{12}C5H12 has three isomers. The displayed formula of one of these isomers (pentane) is:
HHHHH∣∣∣∣∣H−C−C−C−C−C−H∣∣∣∣∣HHHHH \begin{array}{ccccccccccc} & \text{H} & & \text{H} & & \text{H} & & \text{H} & & \text{H} & \\ & | & & | & & | & & | & & | & \\ \text{H} & - \text{C} & - & \text{C} & - & \text{C} & - & \text{C} & - & \text{C} & - \text{H} \\ & | & & | & & | & & | & & | & \\ & \text{H} & & \text{H} & & \text{H} & & \text{H} & & \text{H} & \end{array} HH∣−C∣H−H∣C∣H−H∣C∣H−H∣C∣H−H∣C∣H−HDraw the displayed formulae of the other two isomers.
Ethylene glycol is used as an antifreeze in car cooling systems. A compound Y has this composition by mass:
C=38.7%,H=9.7%,O=51.6% \text{C} = 38.7\%, \quad \text{H} = 9.7\%, \quad \text{O} = 51.6\% C=38.7%,H=9.7%,O=51.6%Use this information to calculate the empirical formula of Y.
The relative formula mass of Y is 62. What is the molecular formula of Y?
19 exam-style questions on Edexcel IGCSE Chemistry Crude oil. Each one has a worked solution and a mark scheme showing where the marks go.