Alkanes (OCR A-Level Chemistry A): Quizzes
📚Quizzes
Practise the questions
10 questions from this quiz
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Practise the questions
10 questions from this quiz
What is the general molecular formula for alkanes?
What is the general molecular formula for alkanes?
Why are alkanes described as saturated hydrocarbons?
Why are alkanes described as saturated hydrocarbons?
They contain only single covalent bonds
How many sigma bonds does each carbon atom form in an alkane?
How many sigma bonds does each carbon atom form in an alkane?
Four
What key property do sigma bonds possess in alkanes?
What key property do sigma bonds possess in alkanes?
Allow free rotation around the bond axis
What is the bond angle in the tetrahedral geometry around each carbon atom in alkanes?
What is the bond angle in the tetrahedral geometry around each carbon atom in alkanes?
Approximately 109.5°
How does boiling point change as the carbon chain length increases in alkanes?
How does boiling point change as the carbon chain length increases in alkanes?
Boiling point increases
Why do longer chain alkanes have higher boiling points?
Why do longer chain alkanes have higher boiling points?
Greater surface area, stronger London forces
How do branched alkanes compare to straight-chain isomers in terms of boiling point?
How do branched alkanes compare to straight-chain isomers in terms of boiling point?
Branched isomers have lower boiling points
In fractional distillation, where do alkanes with lower boiling points condense?
In fractional distillation, where do alkanes with lower boiling points condense?
Near the top of the tower
Which pentane isomer has the lowest boiling point?
Which pentane isomer has the lowest boiling point?
2,2-dimethylpropane (9°C)