Heat of Atomization Ethane: Wavelength to Break C-C Bond

• Raghav Gupta
In summary, the heat of atomization of methane is 360 kJ/mol and the heat of atomization of ethane is 620 kJ/mol. The longest wavelength of light capable of breaking the C-C bond can be calculated using the equation E = hν = hc/λ. For methane, 4 C-H bonds require 360 kJ/mol to break, while for ethane, 1 C-C bond and 6 C-H bonds require 620 kJ/mol. Therefore, the energy required to break 1 C-C bond is 90 kJ/mol.
Raghav Gupta

Homework Statement

The heat of atomization of methane and ethane are 360kJ/moo and 620kJ/mol, respectively.
The longest wavelength of light capable of breaking the C-C bond is (Avogadro number = 6.02 x 1023, h= 6.62 x 1034J s

E = hν = hc/λ

The Attempt at a Solution

I think we should consider energy of ethane only as it only has C-C bond.
What is the use of methane energy?

What bonds are present?

methane is CH4 and ethane is C2H6. All are single bonds.

Let me rephrase the question: bonds between what atoms are present?

Bonds between carbon and hydrogen are present in methane and in ethane between carbon and carbon and also carbon and hydrogen.

So you have two kinds of bonds. Methane contains only one kind, ethane contains two kinds. Within a good approximation bond energy doesn't depend on the molecule.

So now what should I do?
Take E = 360 kJ/mol ?

360 kJ/mol is required to break how many bonds between which atoms? How much per this particular kind of bond is it?

To break 4 C-H bond we require 360 kJ. For 1 C-H bond it is 90 kJ.
For 6 C-H it is 540 kJ.
So for ethane, heat of atomization is 620 kJ.
So for C-C bond it is 90 kJ/ mol
For 1 C-C bond it is 90 / (6.02 x 1023) kJ

mooncrater
Hi!
4 (C-H) bonds require 360kJ/mol...to break them
1×C-C bond+6(C-H) bonds require 620 KJ/mol.
So you can find C-C bond energy.

Raghav Gupta
Thanks all of you, got it.
Mooncrater I think we had written the posts at same time, so you don't realized my 9th post?

mooncrater
Yup...you're absolutely right..heehee tech sometimes messes things up:)

Raghav Gupta

1. What is the heat of atomization of ethane?

The heat of atomization of ethane is the amount of energy required to break the bonds between atoms in one mole of ethane gas and convert it into individual atoms.

2. How is the heat of atomization of ethane measured?

The heat of atomization of ethane is measured by determining the amount of heat released when one mole of ethane gas is formed from its constituent atoms.

3. What is the relationship between heat of atomization and bond strength?

The heat of atomization is directly related to the bond strength of a molecule. The stronger the bond, the higher the heat of atomization will be.

4. What is the wavelength required to break the C-C bond in ethane?

The wavelength required to break the C-C bond in ethane is dependent on the specific conditions and method used to break the bond. It can vary, but generally falls within the ultraviolet or higher energy range.

5. How does the heat of atomization of ethane compare to other molecules?

The heat of atomization of ethane is relatively low compared to other molecules due to the relatively weak bond between its carbon atoms. For example, the heat of atomization of methane, which has only one carbon atom, is higher than that of ethane.

• Biology and Chemistry Homework Help
Replies
4
Views
2K
• Biology and Chemistry Homework Help
Replies
6
Views
2K
• Biology and Chemistry Homework Help
Replies
4
Views
5K
• Biology and Chemistry Homework Help
Replies
3
Views
3K
• Biology and Chemistry Homework Help
Replies
4
Views
2K
• Biology and Chemistry Homework Help
Replies
8
Views
2K
• Biology and Chemistry Homework Help
Replies
2
Views
1K
• Biology and Chemistry Homework Help
Replies
1
Views
8K
• Biology and Chemistry Homework Help
Replies
9
Views
4K
• Biology and Chemistry Homework Help
Replies
2
Views
10K