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F334 ­ The Thread of Life:

The structure of DNA:

DNA is a polymer which is formed from many nucleotides.
A DNA nucleotide is made from 2 sugar phosphate backbones, in between which are
nitrogen bases which can hydrogen bond to each other. DNA is double stranded.
The sugar phosphate…

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To synthesis proteins, the information in the DNA has to get into the cytoplasm of the cell,
and then to the ribosomes.
DNA is too large to leave the nuclear envelope. A copy of the information in the gene is
made in the form of a smaller molecule; this smaller…

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In addition to just the genes, DNA molecules also contain codes which start or stop RNA
production, and other regions which appear to have no function (exons).

The differences between RNA and DNA are:

DNA is made from the deoxyribose sugar, whereas RNA is made from the ribose sugar.

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The rate of reaction can be altered by changing the size of the calcium carbonate chips or the
concentration of the acid.
If the chips are large and in excess, then only a small fraction of the solid reacts and the chips
don't change shape. This means that the calcium…

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concentration of HCl the rate will be halved, if you quarter the concentration, the rate will be

This relationship can be converted into a rate equation by replacing the proportionality sign
with an equals sign and inserting a constant:
Rate = k[HCl]1
k is the rate constant.
If we…

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Now to work out the order of the reaction with respect to X, in this case we need to use
reaction 1 and 2:

The order of this reaction with respect to Y is one, as the relationship between [Y] and rate is
directionally proportional.
The rate equation for the…

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Looking at the graph, the reaction is half completed when the concentration produced is 120
cm3, at this point the concentration of HCl is 1 mol dm-3. The time taken to reach this point is
the half-life of the reaction with a starting concentration of 2 mol dm-3. The half-life…

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The reason for this is that the reaction does not occur in one step, but it occurs in two steps:
The C-Br bond breaks heterolytically:

This only involves C(CH3)3Br, thus its rate is only dependent on [C(CH3)3Br].
The carbocation reacts with OH-:

The reaction for step 2 is much faster…

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If a gas is produced you can collect it in a gas syringe, the volume produced can be used to
follow the rate of a reaction. You could also measure by recording the loss in mass.
You can follow the pH of a reaction if the acid/alkali concentration changes throughout.…

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The mirror images of glycine can be superimposed onto each other; the molecule just has to
be flipped vertically and the isomer is made.
D/L enantiomers
Molecules that show this kind of isomerism are called enantiomers.
Any central carbon atom that is surrounded by four different atoms/groups will form two…


sabrina hasan


will you be making f335 notes on all the modules?

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