3. colorimetry

Question 1

the higher the colour intensity of a solution…

Answer 1

the higher the concentration of the coloured species present

Question 2

what does colorimeter measure?

Answer 2

the absorbance of light of a series of standard solutions at a specific wavelength

Question 3

what does the use of a filter ensure?

Answer 3

that only light of the chosen wavelength passes into the samples

Question 4

which colour of filter should be used?

Answer 4

one which is the complementary colour of the solution being analysed

Question 5

which line should be formed on the calibration graph?

Answer 5

a straight line

Question 6

what is a calibration graph?

Answer 6

a graph of absorbance vs concentration

Question 7

what can a calibration graph be used for?

Answer 7

to the determine the concentration from teh absorbance of a solution

Question 8

what must be done if that sample lies outwith the calibration graph?

Answer 8

the sample must be diluted until it falls within range