Liquids And Solutions

Question 1

How do dilutions in a linear dilutions series differ?

Answer 1

By an equal interval
E.g. 0.1,0.2,0.3 and so on

Question 2

How do dilutions in a log dilutions series differ?

Answer 2

By a constant proportion
E.g. 10-1,10-2,10-3 and so on

Question 3

What does standard curve allow?

Answer 3

Plotting measured values for known concentrations to produce a line or curve allows the concentration of an unknown to be determined from the standard curve

Question 4

How do buffers control the pH of a solution?

Answer 4

Addition of acid or alkali has very small effects on the pH of a buffer, allowing the pH of a reaction mixture to be kept constant

Question 5

When using a colorimeter why does calibration with an appropriate blank need to happen?

Answer 5

To act as a base line value for comparison

Question 6

Using a colorimeter what can use of absorbance be used to determine?

Answer 6

Concentration of a coloured solution using a suitable wavelength filter

Question 7

Using a colorimeter what can use of percentage transmission be used to determine?

Answer 7

Turbidity, such as cells in suspensions