Need Help On some questions!!!

[hazedunks]

The fluorescence of a quinine solution 0.1 ugcm-3 was measured in the presence of various concentrations of bromide ion. Use the data below to calculate the quenching constant for the quenching of quinine florescence with bromide.

10 to the power 3 [BR]/ mol dm-3 0.0 2.0 5.0 11.0 18.0 25.0
fluorescence 77 38 26 15 10 7.6


Also can anyone recommend any good books for statistics in pharmacy.

[giggsy]

Originally Posted by hazedunks

The fluorescence of a quinine solution 0.1 ugcm-3 was measured in the presence of various concentrations of bromide ion. Use the data below to calculate the quenching constant for the quenching of quinine florescence with bromide.

10 to the power 3 [BR]/ mol dm-3 0.0 2.0 5.0 11.0 18.0 25.0
fluorescence 77 38 26 15 10 7.6


Also can anyone recommend any good books for statistics in pharmacy.

lol mr patel

[johnep]

Long time since I filled a quartz cell with a liquid and then shone various frequencies of light through it --spectrophotometry. Quenching is only a distant drum beat from far away now, presume that bromide absorbs light emitted as fluorescence and can thus be used to measure it. Am sure would be in basic photometric text book. All tied up with photons and Planck theory of energy levels.
johnep

[mysteryman]

You need to plot a graph and I think its the intercept or gradient thats the quenching constant. Are you from LSOP? We did something similar to this a while ago. It should be in the notes if so.

[johnep]

Talking of fluorescence reminds me of holidays boating in the Thames Estuary in the 50s. One night sailing from Canvey Island to Whitstable, every movement of the waves brought a blue green glow. Below us we could see the outlines of phosphorescent jellyfish. Above were the moon and stars.
What I would call a 'magic' night.

Perhaps someone here could explain how light sticks work. Puzzles me how they last so long.

Another fascinating chemical reaction was when the demonstrator mixed solns containing Iodine and for some time the colour changed from brownish black for a few seconds and then back to clear.
johnep

[Pharmanaut]

Originally Posted by johnep

Talking of fluorescence reminds me of holidays boating in the Thames Estuary in the 50s. One night sailing from Canvey Island to Whitstable, every movement of the waves brought a blue green glow. Below us we could see the outlines of phosphorescent jellyfish. Above were the moon and stars.
What I would call a 'magic' night.

Perhaps someone here could explain how light sticks work. Puzzles me how they last so long.

Another fascinating chemical reaction was when the demonstrator mixed solns containing Iodine and for some time the colour changed from brownish black for a few seconds and then back to clear.
johnep

Remember Iodine solution in ammonia, collect the crystals and watch them explode as they dry out. Don't try this at home.

[johnep]

We used to drop the crystals on the lab floor. Would explode when the cleaners swept up.
johnep