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Chemistry

A Level

Why do branch chained isomers have lower boiling point than straight chain equivalents?

As branching increases the boiling point decreases because there are fewer points of contact. This also means van der Waals forces are weaker in branch chained isomers and thus less energy is required to ...

Answered by Kishen L. • Chemistry tutor

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What happens to a primary secondary and tertiary alcohol when an excess solution of Potassium Dichromate is added under acidic conditions, state the chemical formula of potassium dichromate?

pottasium dichromate (K₂SO₄) is an example of an oxidising reagent. If added to a primary alcohol, under reflux, carboxcylic acid will form, a secondray alcohol will form a ketone an...

Answered by Christian S. • Chemistry tutor

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i) Write a full balanced equation for (a) the complete combustion of glucose and (b) the incomplete combustion of glucose. ii) Following from part i) suggest a reason (and explain) the difference with the product in reaction (a) and that of reaction (b).

Part I (4 marks) a) C₆H₁₂O₆+ 6O₂-> 6CO₂+ 6H₂O b) C₆H₁₂O₆+ 3O₂ -> 6C...

Answered by Lavan G. • Chemistry tutor

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The boiling points of ammonia (NH3), fluorine (F2) and bromine (Br2) are -33, -188 and +59 degrees celsius respectively. Explain the differences in these boiling points, including the names of any relevant forces and particles.

Differences in boiling points between molecules are due to varying strength of intermolecular forces. From the data given, we know Br₂ must have the strongest intermolecular forces as it has th...

Answered by Alex H. • Chemistry tutor

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Explain and draw the mechanism of the nucleophillic substitution reaction between bromoethane and aqueous sodium hydroxide. How is this reaction different to the elimination reaction which may occur?

The d+ carbon on the bromoethane is susceptible to attack by the OH- nucleophile (negative ion with a lone pair)( the lone pair is very important as this carries out the attack!!!).

When the nucleo...

Answered by Charlotte G. • Chemistry tutor

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