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Chemistry

A Level

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

29470 Views

Explain the trend in boiling points for the group 6 hydrides (O,S,Se,Te). Diagram would be included.

There are 2 factors that affect this problem.
(1) The hydrogen bonding ability of H₂O which increases the boiling point.The partial charges, induced by the higher electronegativity of oxyg...

Answered by Jack R. • Chemistry tutor

31240 Views

Why does propanol have a higher boiling point than propanone, propanal or methyl ethanoate?

Molecules of propanol have a hydrogen directly bonded to a NOF atom (oxygen in this case), which means that they can hydrogen bond with eachother. The oxygen in the other three molecules is only bonded to...

Answered by Katharine W. • Chemistry tutor

33084 Views