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Chemistry

A Level

Rank the following acids according to acid strength, strongest to weakest: HF, HCl, HBr. Explain your reasoning.

Answer: HBr, HCl, HF
Firstly, we must understand what is meant by "acid strength". Simply put, it's the concentration of "free" hydrogen ions (H+) in solution. Acids dissociate (...

Answered by Edgar K. • Chemistry tutor

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Why is a water molecule non-linear?

Valence Shell Electron Pair Repulsion Theory (VSEPR) states that lone pairs repel other lone pairs more so than they do bonded pairs. In water, the oxygen atom has two lone pairs. These two lone pairs rep...

Answered by Harry M. • Chemistry tutor

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Draw an example using a diagram of Carbon, three "Y" substrates and an "L" indicating any leaving group the Sn1 nucleophilic substitution reaction. (3 marks) Which step is fastest (1 mark).

Y₃CL -> [Y₃C]⁺+ L^-(1 mark)Ligand leaves in first step. Can still show ligand as product anion but no need. Also accept any halide as leaving group.
Ste...

Answered by James P. • Chemistry tutor

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Give the molecular formula of benzene. Give the Kekule structure of benzene and then explain why this structure is not correct. Give the accepted structure for benzene (5 marks).

Molecular formula: C₆H₆The Kekule structure (draw on whiteboard in session) - has the hexagonal shape of the ring, with a carbon=carbon double bond on every other carbon-carbon link....

Answered by Ben S. • Chemistry tutor

1887 Views

Explain the trend in ionization energy down a group of the periodic table.

Ionization energy is the energy required to remove one electron from each atom in one mole of gaseous atoms to form one mole of gaseous 1+ ions. This is the following process;
X _g ---> ...

Answered by Euan W. • Chemistry tutor

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