Chemistry Help!

[AgentBlank000]

I have some questions if anyone can help: (basically I need notes for things in the syllabus update 2014)
-What is the concept of electronegativity and how can I apply it to explain the properties of molecules such as bond polarity, dipole moments of molecules, the behaviour of oxides with water and the acidities of chlorine substituted ethanoic acids?
-describe amide hydrolysis on treatment with aqueous alkali or acid.
Thank you in advance for your help.

 

[Farez]

-What is the concept of electronegativity and how can I apply it to explain the properties of molecules such as bond polarity, dipole moments of molecules, the behaviour of oxides with water and the acidities of chlorine substituted ethanoic acids?

Electronegativity is a measure of the tendency of an atom to attract a bonding pair of electrons. It is one of the key concepts in chemistry, and so you should spend some time making sure that you fully understand it - what it means, what causes electronegativity differences, and what effects it has.

Chemguide does a great job in explaining electronegativity, so read this page: http://www.chemguide.co.uk/atoms/bonding/electroneg.html#top

After you're done with that page and are confident about it, read up on eletronegativity in the organic context: http://www.chemguide.co.uk/basicorg/bonding/eneg.html#top

-describe amide hydrolysis on treatment with aqueous alkali or acid.

Amides can be hydrolysed back to the acid and amine used to make them.
Acid hydrolysis uses dil HCl as the catalyst, and you get the amine and the caboxylic acid
Alkali hydrolysis uses NaOH as the catalyst, and you get the amine and the carboxylate ion COO-

Read: http://www.chemguide.co.uk/organicprops/amides/hydrolysis.html

Proteins can be hydrolysed similarly to get back the amino acids.

Read: http://www.chemguide.co.uk/organicprops/aminoacids/proteinhydrolysis.html

 

[AnujaK]

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https://sites.google.com/site/fromatoscom/home