The Simplest Carbon Family
βοΈ The Simplest Carbon Family
Carbon is special. It can bond to four other atoms at once, and it loves bonding to other carbon atoms. This lets it form chains β short chains, long chains, branched chains, rings...
The alkanes are the simplest family of carbon compounds. They're like the "basic" hydrocarbons β just carbon and hydrogen, with only single bonds. Methane (natural gas), propane (BBQ gas), and petrol are all alkanes!
Alkanes are like a chain of people holding hands! Each carbon (person) can hold hands with 4 others. In a chain, they hold two carbons and fill the rest with hydrogens. The longer the chain, the stronger the forces between molecules β that's why longer alkanes have higher boiling points (they "stick together" more)!
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π§ Memory Aid: MEPB β The First Four Alkanes
Remember the first four alkanes using the phrase:
Many Elephants Play Badminton
- Methane β CHβ (1 carbon)
- Ethane β CβHβ (2 carbons)
- Propane β CβHβ (3 carbons)
- Butane β CβHββ (4 carbons)
To use the general formula CβHββββ: double the number of carbons, then add 2. For propane (n=3): 2Γ3+2 = 8. Formula = CβHβ. Check: 3 carbons and 8 hydrogens β correct!
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Quiz Β· Question 1 of 20
What is the general formula for the alkane homologous series?
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