Question

2. Determine the amount of TAE buffer in 40 mL of a 1:5 dilution of TAE with ddH20

ANSWER MUST INCLUDE UNITS WITH PROPER UNIT CONVENTION

A 10 L solution of 0.50 mol/L concentration was prepared by adding 250 mL of stock solution and adjusting the volume to 10 L.

1. What is the dilution performed? (please use 1:A convention)

Answer 1

2. a)

Volume of (1:5) diluted TAE buffer = 40 ml.

So, this dilution was made by adding some amount of TAE stock solution and making up the rest of the volume to 40 ml by adding ddH₂O.

As the dilution is 1: 5,

The TAE stock buffer added = 40 * (1/5) = 8 ml.

Rest ddH₂O added = 40* (4/5) = 32 ml.

2. b)

Diluted solution volume, V₁ = 10 liter.

Diluted solution concentration, S₁ = 0.5 mol/L,

Stock solution volume, V₂ = 250 ml = 0.25 L,

Stock solution concentration, S₂ = ?

We know that, V₁ S₁ = V₂ S₂

So, S₂ =

= 20.

So, Stock solution concentration, S₂ = 20 mol/L

As, we can see that the diluted solution concentration = 0.5 mol/L and the stock solution concentration = 20 mol/L,

So, the dilution of diluted solution = 0.5/20 = 1/40 or 1 : 40