Turn on thread page Beta
    • Thread Starter
    Offline

    16
    Could someone pls help me out with this q? T^T
    I don't understand the mark scheme
    Name:  Screenshot (41).png
Views: 16
Size:  35.2 KBAttachment 726826726828
    Attached Images
     
    • Very Important Poster
    Offline

    21
    ReputationRep:
    Very Important Poster
    (Original post by I-try)
    Could someone pls help me out with this q? T^T
    I don't understand the mark scheme
    Name:  Screenshot (41).png
Views: 16
Size:  35.2 KBAttachment 726826726828
    There isn't a huge amount to say

    it's asking you to find kJ per kg.

    It gives you kJ per mol, and g per mol. Note that kg = 1000g.

    So dividing kJ per mol by g per mol, the mol cancels to leave you kJ per g. But remember, you want kJ per kg.

    You must then multiply this by 1000 (but more intuitively, you are dividing 170g by 1000 to get it into kilograms, then as this 1000 is on the denominator being divided by law of fractions it comes to the top as a multiple.
    • Thread Starter
    Offline

    16
    Oh we had to consider the units. I was looking for a formula >< Thank you!
 
 
 
Reply
Submit reply
Turn on thread page Beta
Updated: February 25, 2018
The home of Results and Clearing

2,316

people online now

1,567,000

students helped last year

University open days

  1. Sheffield Hallam University
    City Campus Undergraduate
    Tue, 21 Aug '18
  2. Bournemouth University
    Clearing Open Day Undergraduate
    Wed, 22 Aug '18
  3. University of Buckingham
    Postgraduate Open Evening Postgraduate
    Thu, 23 Aug '18
Poll
A-level students - how do you feel about your results?

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