chemistry in context
Archiv of answers
Up to now there are 40 answers in the archive:
A sample of air was analysed by explosion with hydrogen in order to determine its percentage by volume of oxygen.25 cm cubeof air was mixed with 100 cm cube of hydrogenand exploded. After cooling at room temp the final volume was 110 cm cube.
what is the relative volumes of hydrogen and oxygen which react?
What is the decrease in volume on reaction?
what proportion of the decrease in volume is due to oxygen?
How many cm cube of oxygen are present in the original air sample?
what is the percentage of oxygen in the original air sample?
Answer:
Hi tawheeda,
I can not simply help with homework, so here are some hints, but the rest must be solved by you. If you have a solution orked out, you can post it here again, and we can discuss if you did it right.
Assuming ideal gas behavior 1 mol of gas has 22400 cm cube.
After mixing the gases you had a volume of 125, after the reaction the volume was reduced to 110 cm cube. Assuming that the volume of liquid water that has formed is negligible, 15 cm cube gas have reacted, according to 2 H2 + O2 --> 2 H2O two molecules of hydrogen react with one molecule of oxygen, or in other words, from your 15 cm cube gas that has reacted, 10 cm cube must be hydrogen, 5 cm cube must be oxygen.
I guess the rest can be done by you yourself, right?
Regards
Oliver Reiser
prjBjh <a href="http://thtassvhvxhe.com/">thtassvhvxhe</a>, [url=http://uctfehnyzhbz.com/]uctfehnyzhbz[/url], [link=http://tujmwfxeinws.com/]tujmwfxeinws[/link], http://uqdlvahxkjyo.com/
Answer:
apJdmI utxkqekxwztu, [url=http://gylrvscbjlfo.com/]gylrvscbjlfo[/url], [link=http://mlastuynyffc.com/]mlastuynyffc[/link], http://ebzjjtfjttmj.com/
how can chemistry affect our politics?
Answer:
Claire,
this is a very broad question.
Environmental issues as well as issues of ressources (alternatives to oil) are certainly both related to cheistry as well as to politics. Drug development also plays a major role in political decisions (health care, how much can it cost).
Regards
Oliver Reiser
