Turn on thread page Beta
    • Thread Starter

    So basically the question is that there is 2.3 grams of a compound , it contains 1.2g of carbon , 0.3g of hydrogen and 0.8 of oxygen, I found the number of moles in each and ended up with 0.1 , 0.3 , 0.65 , now I am confused where i go next to find the formula. Is it CH3O7

    Hi there!

    You've basically got it - just check your calculation for the number of moles of oxygen (it's a bit high - its 0.8/16).

    If you calculate this, then I think you've got the idea - divide all the values by the smallest number.

    Just a tip - when you work out the formula at the end, if the value is 6.5, you would have to double all of your numbers to get whole numbers as you can't disregard 0.5 of the atoms (also, in this case the there should be more H atoms that C and O - again, check O molar calculation!)

    Good Luck

University open days

  • Heriot-Watt University
    School of Textiles and Design Undergraduate
    Fri, 16 Nov '18
  • University of Roehampton
    All departments Undergraduate
    Sat, 17 Nov '18
  • Edge Hill University
    Faculty of Health and Social Care Undergraduate
    Sat, 17 Nov '18
Black Friday: Yay or Nay?
Useful resources

Study tools


Essay expert

Learn to write like a pro with our ultimate essay guide.

Thinking about uni already?

Thinking about uni already?

See where you can apply with our uni match tool

Student chat

Ask a question

Chat to other GCSE students and get your study questions answered.


Make study resources

Create all the resources you need to get the grades.


Create your own Study Plan

Organise all your homework and exams so you never miss another deadline.

Resources by subject

From flashcards to mind maps; there's everything you need for all of your GCSE subjects.


Find past papers

100s of GCSE past papers for all your subjects at your fingertips.

Help out other students

Can you help? Study help unanswered threads

Groups associated with this forum:

View associated groups

The Student Room, Get Revising and Marked by Teachers are trading names of The Student Room Group Ltd.

Register Number: 04666380 (England and Wales), VAT No. 806 8067 22 Registered Office: International House, Queens Road, Brighton, BN1 3XE

Write a reply...
Reputation gems: You get these gems as you gain rep from other members for making good contributions and giving helpful advice.