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VCE Stuff => VCE Science => VCE Mathematics/Science/Technology => VCE Subjects + Help => VCE Chemistry => Topic started by: Jazz_Blue on June 06, 2012, 08:02:25 pm

Title: questions on chemistry
Post by: Jazz_Blue on June 06, 2012, 08:02:25 pm

Starch consists mainly of amylose, which is a polymer made from glucose, C6H12O6, A particular form of amylose has a molar mass 3.62*10^5 gmol-1. A molecule of this amylose can be described as

The answer is a condesation polymer of 2235 glucose molecules.
Can someone explain this to me please?

Title: Re: questions on chemistry
Post by: charmanderp on June 06, 2012, 08:13:20 pm

Glucose has a molar mass of 180. However in a polymer each linkage between glucose molecules (a condensation reaction between hydroxyl groups) in a chain would result in the loss of water, which is a loss of 18 in molar mass.

So (3.62*10^5)/180-18=2234.567901 which rounds up to 2235 glucose molecules.

Title: Re: questions on chemistry
Post by: Jazz_Blue on June 07, 2012, 12:19:42 pm

Thanks!

In DNA, the number of phosphate groups are equals to the number of nitrogenous bases.
Why is it so?

Title: Re: questions on chemistry
Post by: Somye on June 07, 2012, 01:31:39 pm

If you look at a single nucleotide, the number of deoxyribose, nitrogenous bases and phosphate groups are all the same, 1, and hence the number of phosphate groups= the number of nitrogenous bases in DNA

Title: Re: questions on chemistry
Post by: Jazz_Blue on June 07, 2012, 11:16:09 pm

Thanks!

Can someone tell me what is the oxidation and reduction reaction for H2O2?

Title: Re: questions on chemistry
Post by: charmanderp on June 07, 2012, 11:28:34 pm

It's in your data booklet, I think.