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Describe the process of Fractional Distillation

Crude oil heated and fed into the bottom of the fractionating column as a vapour. The column is cooler at the top and hotter at the bottom of the column. The process works using the different boiling and con...
LD
Answered by Lauren D. • Chemistry tutor
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What are covalent and Ionic bonds and how do they differ?

Covalent bonds are formed as a result of the sharing of pairs of electrons between atoms in order to attain a full outer shell. This typically will happen between two non metals. An ionic bond has the same a...
BS
Answered by Ben S. • Chemistry tutor
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Imagine a reaction A for which the values of ΔH and ΔS are both negative. It is known that the absolute value of ΔS is 3 times smaller than the absolute value of ΔH. For what values of T does reaction A occur spontaneously?

We know that a reaction occurs spontaneously when ΔG<0 and that ΔG=ΔH-TΔS. So, we know that the reaction will be spontaneous when ΔH<TΔS.Its is given that ΔH and ΔS are <0 and that |ΔH|=3*|S|. From ...
AC
Answered by Andre C. • Chemistry tutor
2261 Views

a) Describe the nature of ionic bonding. b) State the electron configuration of the Ca (II) ion. c) Outlie why solid calcium is a good conductor of electricity.

a) Ionic bonding is the electrostatic attraction between oppositely charged ions (+ and -). [1]b) 1s 2 2s 2 2p 6 3s 2 3p 6 [1]c) Metallic bonding occurs through delocalized electrons in solid calcium. Those ...
HS
Answered by Hristo S. • Chemistry tutor
3332 Views

A reaction can take place between an acid and an alkali: a) Name this type of reaction. (1 mark) b) Write a word equation that shows the reaction between nitric acid and potassium hydroxide. (1 mark) c) Write the symbolic equation (1 mark)

Answer Answer outline and marking scheme for question: 2 a) Neutralisation. (1 mark) b) nitric acid + potassium hydroxide → potassium nitrate + water(Mark is gained for writing potassium nitrate as the salt)...
SC
Answered by satvir c. • Chemistry tutor
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