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Chemistry

A Level

Describe and explain the difference in base strength between ammonia, primary aliphatic and primary aromatic amines.

Alkyl groups increase basicity because: 1) They push electron density onto the nitrogen atom, which makes the nitrogen lone pair more attractive to hydrogen ions. 2) They stabilise the positive charge on ...

Answered by Sophie B. • Chemistry tutor

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State the crystal structures of SiO2 and CO2 and why one has a higher melting point than the other.

SiO₂ forms a giant covalent structure while CO₂ has a simple molecular structure.In the giant covalent structure of SiO₂, strong covalent bonds hold the atoms together in...

Answered by Fabian T. • Chemistry tutor

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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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