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Diana Cage, whose advice I generally trust, writes in Girl Meets Girl that cheap rubber toys are a bad idea because they contain phylates, which can leach into the bloodstream through mucous membranes.
I always thought those were phthalates. Can anyone double-check me on this? I'm particularly suspicious because the same page misspells 'mucous membranes' as 'mucus membranes'.
I always thought those were phthalates. Can anyone double-check me on this? I'm particularly suspicious because the same page misspells 'mucous membranes' as 'mucus membranes'.
I rediscovered a poem today that I wrote a while back. The compound in question is xenon tetrafluoride (q.v.).
( Not everyone likes even good poetry )
( Not everyone likes even good poetry )
Beer and Carbon Dioxide
Oct. 27th, 2005 04:20 pmA good friend recently asked how much carbon dioxide is created by the brewing of a pint of beer. I'm not entirely sure I got the answer right, but if any science geeks would like to correct me, I'll be glad to update my advice to him.
Here's my attempt at answering, armed with only the Internet and my
misremembered chemistry classes from 1991.
Fermentation produces as many alcohol molecules as it does carbon
dioxide molecules. C6H12O6 -> 2(CH3CH2OH) + 2(CO2)
http://www.yobrew.co.uk/ferment.htm
Beer is typically 3-5% alcohol by weight (0.8 x ABV). I'll take 4% as good enough for this example.
http://www.realbeer.com/library/beerbreak/archives/beerbreak20001005.php
A pint of water is about 473.176475 mL.
http://www.google.com/, search for "1 pint in mL".
A liter of water weighs 1 kg.
http://www.mcps.k12.md.us/curriculum/science/instr/metricwater.htm
Therefore, a pint of water is about 473.176475 grams.
Therefore, a pint of beer (which is mostly water) contains about 4% of that, or 18.927059 grams of alcohol.
The molecular weight of alcohol is 46.069.
http://www.chemie.fu-berlin.de/cgi-bin/molform?CH3CH2OH
Therefore, a pint of beer contains about 18.927059 / 46.069 = 0.411
approx.) moles of alcohol.
The molecular weight of CO2 is 44.010.
http://www.chemie.fu-berlin.de/cgi-bin/molform?CO2
Therefore, 0.411 moles of CO2 contain 0.411 x 44.010 = 18.08811 grams of CO2.
Therefore, if all my other calculations and assumptions are reasonably correct, brewing one pint of beer should generate approximately 18.08811 grams of CO2.
Some of this will escape during brewing and some of it will end up in the beer, making it carbonated, escaping later in the form of fizz or burps.
And that concludes this episode of "Science by the Seat of your Pants".
Here's my attempt at answering, armed with only the Internet and my
misremembered chemistry classes from 1991.
Fermentation produces as many alcohol molecules as it does carbon
dioxide molecules. C6H12O6 -> 2(CH3CH2OH) + 2(CO2)
http://www.yobrew.co.uk/ferment.htm
Beer is typically 3-5% alcohol by weight (0.8 x ABV). I'll take 4% as good enough for this example.
http://www.realbeer.com/library/beerbreak/archives/beerbreak20001005.php
A pint of water is about 473.176475 mL.
http://www.google.com/, search for "1 pint in mL".
A liter of water weighs 1 kg.
http://www.mcps.k12.md.us/curriculum/science/instr/metricwater.htm
Therefore, a pint of water is about 473.176475 grams.
Therefore, a pint of beer (which is mostly water) contains about 4% of that, or 18.927059 grams of alcohol.
The molecular weight of alcohol is 46.069.
http://www.chemie.fu-berlin.de/cgi-bin/molform?CH3CH2OH
Therefore, a pint of beer contains about 18.927059 / 46.069 = 0.411
approx.) moles of alcohol.
The molecular weight of CO2 is 44.010.
http://www.chemie.fu-berlin.de/cgi-bin/molform?CO2
Therefore, 0.411 moles of CO2 contain 0.411 x 44.010 = 18.08811 grams of CO2.
Therefore, if all my other calculations and assumptions are reasonably correct, brewing one pint of beer should generate approximately 18.08811 grams of CO2.
Some of this will escape during brewing and some of it will end up in the beer, making it carbonated, escaping later in the form of fizz or burps.
And that concludes this episode of "Science by the Seat of your Pants".
