Chemistry 9701/23 May June 2017 | Cambridge AS Level Past Papers With Mark Scheme

### 1. Combustion and Empirical Formula:
- Definition of structural isomers.
- Using combustion data to calculate the molecular and empirical formulas of hydrocarbons.
- Calculating the mass of a hydrocarbon sample using the general gas equation.

### 2. Halogens and Their Properties:
- Physical properties of chlorine, bromine, and iodine, including their colors and states at room temperature.
- Explanation of trends in volatility and oxidizing power down the group.
- Reactions of halides with concentrated sulfuric acid, with observations and equations for sodium chloride, sodium bromide, and sodium iodide.

### 3. The Contact Process:
- Calculating enthalpy changes for reactions involving sulfur dioxide and sulfur trioxide.
- Effects of temperature and pressure on the rate of reaction and yield in the Contact process.
- Calculation of equilibrium concentrations and partial pressures in the production of SO3.

### 4. Organic Chemistry - Isomerism and Reactions:
- Drawing structural isomers and identifying compounds with the formula C4H8.
- Understanding geometrical isomerism, including mechanisms of reactions with HBr.
- Identification and drawing of optical isomers produced in reactions, with an explanation of why certain isomers are produced in higher yield.