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Chemistry

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How many peaks would you expect from a Hydrogen NMR of Ethane?

Ethane is a symmetric molecule, therefore both groups of hydrogens occur in the same region and not in two different regions (for example chloroethane would have two different regions). Using the n+1 rule...

Answered by Daniel O. • Chemistry tutor

11938 Views

Explain why the 2nd Electron aiffinity of Chlorine is Endothermic whilst the first electron affinity is exothermic

With the first electron affinity, the chlorine atom is one electron from a full octet ( and is a neutral species). When you add an electron to the chlorine, the negatively charged electron is electrostati...

Answered by Hayden C. • Chemistry tutor

8579 Views

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

2017 Views

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

3756 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

20967 Views