[Whapper2006]

The chemical method of analysis in determination of the blood alcohol content (%BAC) is:

2K2Cr2O7 + 8H2SO4 + 3C2H5OH ---> 2Cr2(SO4)3 + 2K2SO4 + 3CH3COOH + 11H2O

1.10mg of K2Cr2O7 was consumed by the above reaction
I calculated there to be 0.258 milligrams of ethanol in the test sample

how do you calculate the Blood Alcohol Content in this sample (%BAC)??

[enahs]

You would have to know either mass or volume of sample measured.

[Whapper2006]

im nt given any of these though, is there any way to solveit from the chemical equation?

[Borek]

im nt given any of these though, is there any way to solveit from the chemical equation?

No, without additional information this question can't be solved.

[Whapper2006]

my lab manual says the the breathalyzer analyzes a 52.5 ml breath sample, does that help?

[Borek]

How is BAC defined?

[JGK]

my lab manual says the the breathalyzer analyzes a 52.5 ml breath sample, does that help?

That is of no help as a Breathalyzer analyzes alcohol in air (not in blood). To calculate a %BAC you have to know the volume (or weight) of the blood sample analyzed in the titration. From this you can then calculate the %BAC (either as %w/w or %w/v).

[Whapper2006]

ok so I figured it out.  I got the answer by ratio.  .25mg of ethanol = .10% BAC
I got .258 mg of ethanol

so .25x=(.258)(.10)

BAC is .1032%

[Borek]

im nt given any of these though, is there any way to solveit from the chemical equation?

my lab manual says the the breathalyzer analyzes a 52.5 ml breath sample, does that help?

.25mg of ethanol = .10% BAC

You were given a lot of information, but you have chosen to not share it with us. That's the simplest way of wasting our time, you know.

[Whapper2006]

we had class today and the professor gave us that ratio. I didn't know it beforehand and thats why me and other classmates were having trouble with this.

sorry for wasting your time but to be honest the biggest help was everyone telling me that this problem couldn't be solved unless i had more information, which made me therefore seek that information, which I received today and solved the problem. so thank you.