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Chemistry

A Level

Draw the mechanism for the reaction of an acid chloride with an alcohol to form an ester

First thing to remember is that when drawing curly arrows, the arrows start where the electrons start and finish where the electrons end up. For this reaction the lone pair of electrons on the oxygen from...

Answered by Hannah R. • Chemistry tutor

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State an explain the result of an increase in temperature on the following equilibria: N2 (g) + 02 (g) <-> 2 NO (g) (delta H = +180kJmol-1)

An increase temperature favours the endothermic direction of an equilibrium reaction; this is because there is more energy in the surroundings to accommodate for the energy that will be taken into the sys...

Answered by Samuel G. • Chemistry tutor

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Describe and explain the trend in boiling points in the first four hydrogen halides

HF has the highest boiling point this is followed by HI, then HBr with HCl having the lowest boiling point of the four molecules. This is because HF is able to form Hydrogen bonds whereas the other three ...

Answered by Theo M. • Chemistry tutor

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What 2 reagents are required to form NO2+ (state conditions)? Write an equation for this reaction.

Concentrated sulphuric acid (H₂SO₄) and concentrated nitric acid (HNO₃).H₂SO₄ + HNO₃ -> HSO₄^- + H₂NO

Answered by Eleanor C. • Chemistry tutor

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BeCl2 has a linear shape with a bond angle of 180 degrees, where as H2O has a bent shape with a bond angle of 104.5 degrees. Explain why these molecules have different shapes despite having the same general formula of AB2.

BeCl2 contains 2 bonding pairs of electrons which arrange themselves as far away as possible to minimise the electron repulsion between them, giving a bond angle of 180 degrees and a linear shape. H2O als...

Answered by Sam R. • Chemistry tutor

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