Dilutions, Molarity and Titrations PDF

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Summary

This lecture covers the practical aspect of dilutions, molarity and titrations in the first year of cell biology and biochemistry for a range of different courses....

Description

Cell Biology and Biochemistry: Practical: Dilutions, Molarity and Titrations:

Dilutions: To make a dilution of anything, you will require… Materials:    

A stock solution (this contains a concentrated version of what ever you want to dilute) Containers of the correct size A liquid to dilute the solution Equipment to measure the volumes required

Knowledge:    

The concentration of your “stock” solution that you have The concentration of the “working” solution that you want The volume of the “working” solution you require The volume of the “stock” solution that needs to be taken to create the required concentration

A single dilution:

0.01mL – 10microlitres 1000 microlitres in 1 millilitre

Molarity:   

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1 mole of a substance is a relative molecular mass of that substance in grams 1 mole of a substance contains 6.02 x 1023 molecules of that substance A molar solution contains 1 mole of a substance in 1 litre of a solution. The number of moles in a solution is termed the morality of the solution Relative molecular mass (RMM) = cumulative atomic mass of all the atoms in a molecule. RMM is sometimes referred to as: RAM (relative atomic mass) or FW (formulaic weight) Molarity takes account of the number of molecules A mole is an SI unit that is used to count molecules 1 mole of anything will always have 6.02 x 10 23 molecules 1 mole can be obtained by weighting the relative atomic mass of a molecule out in grams The relative atomic mass is the sum of total of all the atomic masses of all the atoms in a molecule (sometimes referred to as RMM) Molarity is the number of moles of something in a litre (i.e. mols dm3). It can be thought of as being the concentration of molecules in a solution

Clinical chemistry:   

Clinical chemistry measure components of blood (other than cells) Reference ranges are used to define health and disease Multiple units are used

pH:   

pH is the measure of hydrogen ions Logarithmic scale Buffering is a resistance to pH

Molarity:  

1 mole of a substance in the relative molecular mass of that substance in grams A molar solution is 1 mole of a substance in 1 litre of liquid – measured in mol dm-3

Glycylglycine:   

Dipeptide 2 glycine’s 1 amino group

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1 carboxyl group...