April 21, 2019, 06:40:16 AM
Forum Rules: Read This Before Posting

Topic: Organic question  (Read 421 times)

0 Members and 1 Guest are viewing this topic.

Tamer7

• Very New Member
• Posts: 1
• Mole Snacks: +0/-0
Organic question
« on: January 30, 2019, 09:13:00 AM »
How can i get the value of “n” for an aclcohol such that the percentage by mass of oxygen equals 21.6%?

Borek

• Mr. pH
• Deity Member
• Posts: 24943
• Mole Snacks: +1636/-395
• Gender:
• I am known to be occasionally wrong.
Re: Organic question
« Reply #1 on: January 30, 2019, 09:21:27 AM »
No idea which "n" (there is one obvious candidate, but in general question is pretty ambiguous), but the general approach is to express oxygen fraction as a function of "n" and to solve for the unknown.
ChemBuddy chemical calculators - stoichiometry, pH, concentration, buffer preparation, titrations.info, pH-meter.info, PZWT_s1

Vidya

• Full Member
• Posts: 723
• Mole Snacks: +42/-60
• Gender:
• Online Chemistry and Organic Chemistry tutor
Re: Organic question
« Reply #2 on: February 04, 2019, 12:57:16 AM »
How can i get the value of “n” for an aclcohol such that the percentage by mass of oxygen equals 21.6%?
General formula of alkanol is CnH2n+1OH
So which means : CnH2n+2 O
If O is 21.6 % then remaining mass is due to C and H
Moles of carbon and H are in the ratio of
n:2n+2
Now use your algebra skill and mole concept of chemistry to solve it.