jhuk
Badges: 7
Rep:
?
#1
Report Thread starter 1 year ago
#1
Can someone please explain part b to me
Attached files
0
reply
ChemistryWebsite
Badges: 10
Rep:
?
#2
Report 1 year ago
#2
For each equation construct a Hess's Law 'triangle'. You have the enthaplies of formation for the reactants and products in each case, so write the (balanced) elements below each equation.
Use Hess's Law to work out the enthalpy of combustion via the enthalpies of formation for the reactants and products.
0
reply
charco
Badges: 17
Rep:
?
#3
Report 1 year ago
#3
(Original post by jhuk)
Can someone please explain part b to me
Write out the equation for enthalpy of combustion of each compound.

Use

(sum of) formation enthalpy of products - (sum of) formation enthalpy of reactant = enthalpy of reaction.
0
reply
jhuk
Badges: 7
Rep:
?
#4
Report Thread starter 1 year ago
#4
I dont understand how to construct the triangle, I have balanced all the equations
0
reply
ChemistryWebsite
Badges: 10
Rep:
?
#5
Report 1 year ago
#5
(Original post by jhuk)
I dont understand how to construct the triangle, I have balanced all the equations
You construct like the example.

(You should probably include the state symbols, unlike my example!)
Attached files
1
reply
jhuk
Badges: 7
Rep:
?
#6
Report Thread starter 1 year ago
#6
Thank you
0
reply
ChemistryWebsite
Badges: 10
Rep:
?
#7
Report 1 year ago
#7
(Original post by jhuk)
Thank you
You're welcome!

Hopefully when you did the Hess's triangle for hydrogen you noticed a relationship;
A relationship between the enthalpy of combustion and the enthalpy of formation of water.
Why is that relationship there? Because hydrogen (and the oxygen required in combustion) are elements, so their enthalpy of formation is zero.
0
reply
X

Quick Reply

Attached files
Write a reply...
Reply
new posts
Back
to top
Latest
My Feed

See more of what you like on
The Student Room

You can personalise what you see on TSR. Tell us a little about yourself to get started.

Personalise

University open days

  • Norwich University of the Arts
    Postgraduate Open Day Postgraduate
    Thu, 23 Jan '20
  • SOAS University of London
    Development Studies, Interdisciplinary Studies, Anthropology and Sociology, Languages, Cultures and Linguistics, Arts, Economics, Law, History, Religions and Philosophies, Politics and International Studies, Finance and Management, East Asian Languages & Cultures Postgraduate
    Sat, 25 Jan '20
  • University of Huddersfield
    Undergraduate Open Day Undergraduate
    Sat, 25 Jan '20

How many uni open days have you been to/did you go to?

0 (50)
26.6%
1 (30)
15.96%
2 (34)
18.09%
3 (26)
13.83%
4 (12)
6.38%
5 (16)
8.51%
6 (4)
2.13%
7+ (16)
8.51%

Watched Threads

View All
Latest
My Feed