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Chemistry

A Level

How do I systematically name alkanes?

When naming alkanes, I like to follow a set of rules:Firstly, draw out the molecule structurally showing all bonds present. Next identify the longest carbon chain. The longest carbon chain determines the ...

Answered by Nora M. • Chemistry tutor

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Explain the trend in first ionisation energy as you go across Period 3

Overall, the first ionisation energies will increase. This is because as you go along the period, the atomic number increases and this causes a stronger electrostatic attraction between the outer electron...

Answered by Charles W. • Chemistry tutor

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Sort the following compounds in order of increasing boiling point and explain your reasoning: hydrogen, hydrogen fluoride and hydrogen bromide

Order: hydrogen fluoride > hydrogen bromide > hydrogen.Hydrogen fluoride contains a hydrogen atom bonded directly to a fluorine atom. The fluorine is highly electronegative and so pulls the bonding ...

Answered by Alex M. • Chemistry tutor

4459 Views

a) How can an element be classified as a transition metal, considering only electronic arrangement? (1 mark) b) In terms of electrons, why is aqueous copper(II) sulphate solution red? (3 marks) c) EDTA is a bidentate ligand. What is a bidentate ligand?(2)

a) Partially filled/incomplete d shell.
b) Light is absorbed by an electron, exciting it and is promoted to a higher energy d orbital. The colour seen is the complimentary colour of that absorbed (in...

Answered by James O. • Chemistry tutor

1838 Views

25cm^3 of 0.1M NaOH is reacted with 0.01M HCl until the equivalence point is reached. What volume of HCl was required to be added?

0.025 dm^3 x 0.1 mol dm^-3 = 0.0025 molsince mols must be equal:mols of HCl = 0.0025/0.01 =250cm^3To get to the answer I would first check the student was first able to identify the key words and numbers ...

Answered by Georgina W. • Chemistry tutor

2331 Views