You are Here: Home

# enthalpy change of a reaction watch

1. An excess of copper powder was added to 50.0cm of 0.60 mol dm AgNO3. The temperature increased from 24 to 32. Find the enthaply change for the reaction.

I did 100x 4.18x 8= 3344

2. I've moved this to the appropriate forum where you should get more responses.
3. (Original post by thapki123)
An excess of copper powder was added to 50.0cm of 0.60 mol dm AgNO3. The temperature increased from 24 to 32. Find the enthaply change for the reaction.

I did 100x 4.18x 8= 3344

silver ions are the limiting reagent and there are 0.6 * 0.05 mol of them = 0.03 mol

ΔE = -mcΔT = -0.05 x 4.18 x 8 = -1.672 kJ

Hence energy per mol of silver ions = -1.672/0.03 = -55.7 kJ

But if you wish to have the energy change for the stoichiometric reaction as written then this shows 2 mol of silver ions:

2Ag+ + Cu --> 2Ag + Cu2+

So, you would need to multiply the answer by 2 = -111.5 kJ

### Related university courses

TSR Support Team

We have a brilliant team of more than 60 Support Team members looking after discussions on The Student Room, helping to make it a fun, safe and useful place to hang out.

This forum is supported by:
Updated: November 4, 2015
Today on TSR

### Edexcel GCSE Maths Unofficial Markscheme

Find out how you've done here

### AQA Maths Paper 1 exam discussion

Poll

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