How Do You Calculate Blood Alcohol Concentration

How to calculate blood alcohol content?

Well.. you could try the somewhat quick and dirty approach that the police use
.. 1 mL blood contains as much alcohol as 2100mL breath

so that in 2100mL "breath" or "1mL blood".. you would have this much alcohol (EtOH)

.. 2.100L breath.. 0.0195 mol EtOH.. .46.07g EtOH
.. --- --- --- --- --- x ---- ---- --- ---- ---- x -- --- --- --- --- = 1.886g EtOH
.. .. .,... 1.. .. ..... . .... ..1L breath .. ... ... .. mol EtOH

and that is the amount you would find in 1mL of blood so that
.. ... .. .1.886g... .100.. .. 189g EtOH
BAC = --- ----- x --- --- = ----- ----- ----- ---- = 189 = death... ..many times over
.. .. .. .... 1mL.. .. .100.. .. .100mL blood

so where did we go wrong in the calcs? Why did we get 189 instead of something like 0.189? let's take at look at BAC = 0.08 for a second

.. 0.08g.. .. ....... ..1mol. ... .. 1mL blood.. ... . 1000mL breath
.--- - --- ---- --- x ----- ----- x -- --- ---- --- --- x -- ---- --- --- ---- --- = 8.27x10^-6 M EtOH in breath
..100mL blood... 46.07g... .2100mL breath.. .... .1L breath

OOPS.. See that x10^-6M? you have 0.0195M in your problem statement.. 1000x tooo high!
.. are you sure about that 0.0195M? are you sure it's not 0.0195x10^-3 M
.. or perhaps.. 0.0195mM ?... millimolar?

let's redo that calcs with that assumption.. this time, I'm going to use 1 equation.

.. 0.0195millimole.. 46.07x10^-3g.. .... .1L air.. .. .2100mL air.. ..100... .. .. 0.189g
.. -- --- --- ----- --- x --- --- ---- --- -- x ---- ----- ---- x -- ---- ---- --- x ---- -- = --- ---- ----- --
.. .. ... ..L air.. ... .. . ... millimole.. ... .1000mL air... 1mL blood... .100... . 100mL blood

or simply BAC = 0.189....

the perp will be arrested, jailed, forced to stand trial, ordered to not drive until 21, fined $10,000, beat, tortured, and left for dead. In the event he does it again, the courts will take his car and sell it at auction, toss him in a cell with a perp like Richard Speck and ignore whatever happens next.

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How do you Calculate your Blood Alcohol Content?

Need to know if you are male or female. Males can drink more because they have more of the dehydrogenase enzymes that break down alcohol in the liver than girls do. They also have more water in their bodies to dilute the alcohol. A 100 lb female is at .10, over the legal limit of .08, after the 2nd drink. A 100 lb. male is just at the legal limit at the 2nd drink. A drink is either 1.25 oz of 80 proof liquor, 1 12 oz beer or 5 oz of wine. So I definitely would not drive if you're drinking anything at all, especially 100 proof or 160 proof alcohol, you would be over the legal limit at 1/2 to 1 drink. Whatever you do, do not drive. You are significantly impaired whether you feel like you are or not after just 1 drink. Remember if you drive, you will either end up in jail, best case scenario, or end up dead or killing some other innocent person and go to prison for a very long time. Just not worth it. Be careful drinking like that with a wt of only 100 lbs, you drink too much you could end up with alcohol poisoning, which can be fatal. Check out this link, it gives you the BAC calculator.

http://bloodalcoholcalculator.org/index....

Blood alcohol concentrations?

0.05 You enjoy talking to other people.
0.1 You continue talking to other people after they ask you to leave.
0.2 You are talking to statues.
0.4 You are talking to people no one else can see.

Calculate the Blood Alcohol Content in this sample?

I'm chem, not med, so I hope this is as straightforward as it looks. (if not, ignore me)

BAC is measured by mass(alcohol) per volume(blood), or mass per mass.

So you need a value for mass or volume of the sample. Density of blood is 1.06 g/mL, if you need to convert. Equation is simple,

Ma = mass alcohol (0.258 mg in this case)
Vs = volume of sample
Ms = mass of sample

(Ma/Vs) * 100% = BAC
Vs and Ms are interchangeable, just give you different units.

Calculating blood alcohol conc in mmol/L?

Hi there I'm having trouble with what is very likely a simple question:

how would you calculate blood alcohol concentration in mmol/L?

I have the BAC in mg/dL but I'm not sure if this is relevant.

My attempt is as follows;

Mr of ethanol is 46.07 (although we were just given it as 46 so this should be sufficient)

Mr (46.07) X volume used (which was 0.01ml) / total volume (which was 3.01)

The idea is we are calculating the BAC from samples from two individuals, which we have done in mg/dL and also as % (w/v).
but I'm not sure if Im even on the right lines as maths is not a strong point of mine

Thanks for any help

What is the concentration of alcohol, in terms of molarity, in blood if the BAC is 0.08?

The concentration of alcohol (CH3CH2OH in blood, called the "blood alcohol concentration" or BAC, is given in units of grams of alcohol per 100mL of blood.
The legal definition of intoxication, in many states of the United States, is that the BAC is 0.08 or higher.

What is the concentration (Molar) of alcohol, in terms of molarity, in blood if the BAC is 0.08?

If blood alcohol concentration does not depend on what you drink, then what does it depend on?

This an ACCURATE description related to blood alcohol and "testing". The breath test for "legal" alcohol level is abnormally high early on especially right after alcohol consumption because of gastric evaporation when you blow into the device. Some individuals have had an illegal level after consuming only one glass of wine and being pulled over right after their dinner. The breath test as stated is typically abnormally high early on and when someone is really intoxicated, well over the legal limit, it tends to be lower than the actual blood test(BAC-blood alcohol concentration) but still will register OVER the legal limit. The blood test is the ONLY accurate measurement. Under the law in all 50 states a driver is REQUIRED, if asked, to take a field sobriety test. However, you have the right in all 50 states to respectfully refuse to take the breath test and request the blood test BUT are required to submit to testing of some sort. If the blood test shows that you are legally intoxicated (.08 or greater), in most states, you will be liable for the cost of the testing. If you are NOT legally drunk you will typically not have to cover the cost.
A good rule of thumb to figure out if you are legally drunk(> or = .08), is that each ounce(shot) of alcohol(not a heavy proof of something like Everclear) or 8oz beer or 8oz glass of wine equals .02. The body outside of kidney or liver disease will eliminate .01 per hour. So if you have had 6 mixed drinks(1 oz alcohol in each) over 6 hours, your BAC would be 6x.02 - 6x.01 = .12 - .06 = .06 where you would be BELOW the legal limit. Factors such as body weight or build are irrelevent and don't influence the BAC.
One must remember than some sort of impairment can occur with just one drink. The best thing to remember is safety first and don't drink and drive. If you go out for a couple drinks, be out for the time it takes to eliminate the alcohol from your blood BEFORE you drive home and you will know for sure that you are safe and not impaired.