00:01
So we're told we have this 1 .5 gram sample of conian, and we dissolve it in 10 milliliters of ethanol, and it is placed in a sample cell with a 5 centimeter path length.
00:16
And they tell us the observed rotation at the sodium d -line was plus 1 .21 degrees, and we want to calculate the specific rotation for conium.
00:30
So to do that, we need to use this equation right here, but before we do that, we need to calculate a couple of things.
00:36
So we're already told that our observed rotation, which is alpha, plus 1 .21.
00:45
Now we need to figure out, well, l and our concentration.
00:48
So to get the concentration, we're just going to divide these two.
00:51
So c is going to be 1 .5 grams divided by 10 milliliters.
00:59
And doing this should give us 0 .150 grams per milliliter, which this would be the same thing as 1 .5, or 0 .150 grams per centimeters cubed.
01:21
Then the next thing we're going to need to do is convert our l to decimeters.
01:30
So remember to do this, what we're going to need to do...