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Suggest why Phenol is more reactive than Benzene in Electrophillic Substitution

With phenol, the oxygen atom is directly attached to the delocolised pi system in phenol, as a result the lone pair on this oxygen is incorporated into this delocolised pi system in phenol, increasing it'...

Answered by Hayden C. • Chemistry tutor

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Why does reacting a bromoalkane with ammonia result in a quaternary ammonium salt and not an amine?

To explain this question let us use an example of reacting Bromoethane (CH3CH2Br) with ammonia (NH3). As bromine is more electronegative than carbon (electronegativity being the ability of an element to a...

Answered by Henry D. • Chemistry tutor

3407 Views

You have 3.51g of hydrated zinc sulphate. You heat up the zinc sulphate until all the water has evaporated from it. The weight after heating is 1.97g. Find how many H2O molecules per zinc sulphate molecule there are in the hydrated form of it.

Write down the equation: ZnSO4xH2O --> ZnSO4 + xH2O 2. Calculate the masses: 3.51g --> 1.97g + 1.54g 3. Calculate the number of moles, using the molar mass of water and zinc sulphate: 1.97g = ...

Answered by Olivier S. • Chemistry tutor

19928 Views

What is entropy and how is it used in chemistry?

Entropy (S) is a measure of disorder in a system. Any process, in this case a chemical reaction, is said to entropically favoured if the overall disorder in the system increases. This is usually when ther...

Answered by Kashf S. • Chemistry tutor

2188 Views

What is the trend in atomic radius of the elements across Period 3 and why does this occur?

The atomic radius of the elements decreases from sodium to argon. This is because the number of protons increases (sodium has 11, argon has 18) so the nuclear charge increases. Therefore, the attraction b...

Answered by Chloe G. • Chemistry tutor

46470 Views