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Chemistry

A Level

Define the term Covalent Bond

A covalent bond is formed by a shared pair of electrons between two atoms.

Answered by Rex O. • Chemistry tutor

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Give the reagents required for the nitration of toluene (methylbenzene) to 2,4,6-trinitrotoluene and provide a mechanism.

The reagents needed are sulphuric acid and nitric acid. It may be useful to notice that nitric acid here acts as a stoichiometric reagent, in that it is used up in the reaction to nitrate the toluene, but...

Answered by Alex A. • Chemistry tutor

6806 Views

Explain Le Chatelier's Principle and the factors that affect the position of equilibrium

Le Chatelier's principle states that is there is a change in concentration, pressure or temperature, the equilibrium will move in order to counteract the change. Firstly temerature - in an reversible reac...

Answered by Suraiyya J. • Chemistry tutor

16932 Views

Describe briefly the nature of metallic bonding and use this to explain why metals are malleable (can be hammered into shape) and conduct electricity

Metallic bonding occurs as a result of the electrical attraction forces between the protons in the nuclei of the metal species and the delocalised electrons (which form a sea of electrons surrounding the ...

Answered by Miroslav A. • Chemistry tutor

12876 Views

State what is meant by the term 'first ionisation energy' and explain why the first ionisation energy of barium is lower than that of calcium

First ionisation energy is the energy required to remove one mole of electrons from one mole of gaseous atoms, to produce one mole of gaseous ions each with a (+1) charge.

Barium has more energy le...

Answered by Varsha S. • Chemistry tutor

4752 Views