[zetic]

Hi, It is a two part question.

1- I am trying to work out the heat of formation for Calcium Hypochlorite and Sodium Hypochlorite using the following formulas.

a- Cl2 + Ca(OH)2 --> Ca(OCl)2 + CaCl2 + H2O

b- Cl2 + NaOH --> NaCl+NaClO+H2O

Can someone show me how to calculate these step-by-step. I tried to plug in the individual values of each compound but does not seem to be working.

2- I am trying to figure out of is possible to make Sodium Hypochlorite using Sodium Carbonate or Sodium Bicarbonate. Any ideas on this matter would be a great help. Thx!

Tom

[Borek]

I tried to plug in the individual values of each compound but does not seem to be working.

What values, and into what? Please show details of what you did.

[zetic]

To find heat of formation for Calcium Hypochlorite, I did:

2Cl2 + 2Ca(OH)2 --> Ca(OCl)2 + CaCl2 + 2H2O
With the values of
0 + 2x(-986.09) --> ? + -795.8 + 2x(-285.
? = -604.78 , is it correct?

Cl2 + Na(OH) --> NaCl + NaClO + H2O
0 + 2x(-469.15) --> -407.27 + ? + -285.8
? = -245.23, but the energy I found on the internet is -347.3?

[billnotgatez]

2Cl₂ + 2Ca(OH)₂  Ca(OCl)₂ + CaCl₂ + 2H₂O

Cl₂ + Na(OH)  NaCl + NaClO + H₂O

@zetic
I rewrote your equations using the editing features in the posting window
Are they balanced?

You also might want to reread the forum rules
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Forum Rules: Read This Before Posting

[zetic]

@billnotgatez

Thank you for your inputs.
Actually, I think that I made a mistake when writing the sodium hydroxide + chlorine gas equation. However, when I make the calculations, I am aware that is 2 Na(OH) for the reaction, hence, the 2x(-469.15) but which does not give me the same heat of formation for sodium hypochlorite found on the internet of -347.3 (far from it). So, I am wondering if there is anything I am doing wrong in these calculations.

[zetic]

To others, please give me some insights.

Also, I would like others to comment rather reacting calcium hypochlorite with sodium carbonate as a substitution to form sodium hypochlorite and calcium carbonate can be done. (Perhaps, calcium carbonate will be deposited at the bottom of the beaker when reacted?)

I have looked into finding a way to produce 10% solution of sodium hypochlorite for use, which is not available in my market / electrolysis membrane machines are expensive and chlorine gas is not an option. So, it would be a great help if someone can give me some insights on how to make sodium hypochlorite in a simple solution reaction.

(I have also looking into attempting to modify SDIC or TCCA. Which turns into a much more complex problem.)

[unsu]

Hi zetic,

When you are trying to find the unknown enthalpies of formation of Ca(OCl)₂ and NaOCl, you need to know the enthalpies of the reactions. That is why you are not getting the right answer.

[Borek]

0 + 2x(-469.15) --> -407.27 + ? + -285.8

What are these numbers?

Please pay attention to being precise, you either assume everything is obvious (it isn't) or you not aware it is ambiguous (it is).

[zetic]

@unsu thx for your help. I know i was forgetting something~!
@Borek, you are absolutely right. Will pay close attention in the future