Cumene is a cmpd containing only C and H that is used in the production of aceton and phenol in the chemical industry. Combusetioni of 47.6 mg of cumene produces some Co2 and 42.8 mg of water. The molar mass is between 115-125. determine the empirical formula and molecualr formula.Please show work
i seriously dun get it
2007-08-22 18:26:34 · 2 answers · asked by Krazym0nkey 2 in Science & Mathematics ➔ Chemistry
If water weights 42.8 mg, and you know all the oxygen comes from the air, and you know how many Cumen molecules you had previous to the combustion (because you have the molar weight and the Avogadro number), then, you know how many hydrogen atoms you had in a "Cumene" (is that right) proportion of a mole.
You know its molar mass is between 115 and 125, so substract the weight equivalent from the hydrogen (you have the weight of a fraction, calculate the whole), and you have the weight of carbon. Divide again, and you have the number of C.
The rest is left to you, because you'll have to say if it has or not double or triple bonds.
I hope this helps. If not, you can check the Hart and Hart book.
Good Luck, man
2007-08-22 18:40:17 · answer #1 · answered by Etienne 4u 2 · 0⤊ 1⤋
Multiply 42.8 by 2/18 to get the mass of H. Subtract this from 47.6 to get the mass of C.
Now you are on your way!
2007-08-23 03:19:40 · answer #2 · answered by Gervald F 7 · 0⤊ 0⤋