Starter quiz
- Which of the following is a characteristic of molecular compounds?
- Composed of metal atoms
- Made from metal and non-metal atoms
- Formed from non-metal atoms ✓
-
- In distillation, what characteristic is primarily used to separate substances in a mixture?
- Density
- Boiling point ✓
- Molecular weight
- Colour
-
- Carbon will form a maximum of ______ bonds to other atoms.
- '4' ✓
- When oxygen atoms bond together to make diatomic oxygen molecules (O₂), this is known as a double covalent bond.
- True ✓
- False
- Which property increases as the strength of intermolecular forces increases?
- Electrical conductivity
- Malleability
- Boiling point ✓
- Solubility in water
-
- Select all the true statements about simple molecular substances.
- Low melting points ✓
- Cannot conduct electricity ✓
- High melting points
- Conduct electricity only when molten or dissolved
- Conduct electricity all the time
-
Exit quiz
- Which elements make up hydrocarbons?
- carbon ✓
- hydrogen ✓
- oxygen
- nitrogen
-
- Which of the following are correct statements about compounds in the same homologous series?
- have the same general formula ✓
- have similar chemical properties ✓
- show a trend in physical properties ✓
- neighbours in the series differ by -CH₃ group
- are always chain structures
-
- Saturated hydrocarbons are called ______. They are saturated as they only contain single bonds between the carbon atoms.
- 'alkane' ✓
- Which of the following is not a use of hydrocarbons?
- fuel
- solvent
- feedstock
- detergent
- food ✓
-
- Which of the following is the correct general formula for alkanes?
- CnH2n+2 ✓
- CnH2n
- C2nHn+2
- C2n+2H2n
- CnHn
-
- Order the following hydrocarbons by carbon chain length. Start with the shortest carbon chain.
- 1⇔methane
- 2⇔ethane
- 3⇔propane
- 4⇔butane
Worksheet
Presentation
Video
Lesson Details
Key learning points
- Hydrocarbons are simple covalent compounds made of hydrogen and carbon atoms only.
- Hydrocarbons are found in crude oil, and are used as fuels and feedstock.
- Alkanes consist of chains, or rings, of carbon atoms that are each also bonded to hydrogen atoms.
- Alkanes are a homologous series of hydrocarbons, with the same general formula with a trend in properties.
- The general formula for an alkane is CnH2n+2.
Common misconception
Students often think that the prefix hydro- in the term hydrocarbons means they contain water; also that hydrocarbons and crude oil are synonymous.
Use diagrams to show hydrocarbon composition and compare crude oil to pure hydrocarbons, highlighting the difference visually.
Keywords
Hydrocarbon - Simple covalent compounds made of carbon and hydrogen atoms only.
Feedstock - Raw materials used in chemical processes to produce other substances.
Alkane - Saturated hydrocarbons (have only single bonds between carbon and hydrogen atoms).
Homologous series - Compounds that have the same general formula, with neighbouring molecules often differing by CH₂, showing similar chemical properties and physical property trends.
Nomenclature - A collection of rules for naming things (in chemistry it refers to the naming of chemical substances).