Chemistry Why NaCl Instead of 2NaCl in Reactions?

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The discussion clarifies the correct balancing of the chemical equation involving sodium carbonate (Na2CO3) and hydrochloric acid (HCl). The correct product is NaCl, not 2NaCl, because sodium chloride exists in a one-to-one ratio of sodium and chloride ions. The confusion arises from the need to balance the equation, which involves ensuring the number of each type of atom is equal on both sides. Participants emphasize that the equation given in some resources may incorrectly suggest a typo, but the focus should be on achieving a balanced equation. Understanding the dissociation of ionic compounds in solution is crucial for correctly representing the reaction.
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Homework Statement
An aqueous solution of Na2CO3 is added to dilute hydrochloric acid. The
resulting carbonic acid, H2CO3, breaks down to form CO2 gas and H2O. Complete and balance the molecular equation for this reaction
Relevant Equations
/
Hello,

Can I get some clarification on why it is NaCl and not 2NaCl as a product please?
Thanks in advance!

1663847665138.png


I had ##Na_2CO_3 + 2HCl## --> ##2NaCl + CO_2 + H_2O## instead. Why is this not correct?
I have this as shouldn't the number of chlorine and sodium atoms be the same in reactant and product side?
 
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simphys said:
Homework Statement:: An aqueous solution of Na2CO3 is added to dilute hydrochloric acid. The
resulting carbonic acid, H2CO3, breaks down to form CO2 gas and H2O. Complete and balance the molecular equation for this reaction
Relevant Equations:: /

Hello,

Can I get some clarification on why it is NaCl and not 2NaCl as a product please?
Thanks in advance!

View attachment 314453

I had ##Na_2CO_3 + 2HCl## --> ##2NaCl + CO_2 + H_2O## instead. Why is this not correct?
I have this as shouldn't the number of chlorine and sodium atoms be the same in reactant and product side?
That is what I get also. Perhaps we are missing something obvious, @Borek will spot it?
 
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The 2 is missing, simple typo.
 
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The answer given does not have the same number of Na and Cl atoms on both sides of the reaction, so it must be wrong.
 
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DrClaude said:
The answer given does not have the same number of Na and Cl atoms on both sides of the reaction, so it must be wrong.
What I assumed as well, thank you.
 
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DrClaude said:
The answer given does not have the same number of Na and Cl atoms on both sides of the reaction, so it must be wrong.
hey @DrClaude (or anybode else :) )I didn't want to open another thread for this small question but I wanted to ask the following:
1663858641476.png

it's about question (a): I was wondering what the reason 'd be not to write ##Na_2Cl_2## instead of 2NaCl?
my possible explanation, because the ionic compounds dissociate in water(aq solution) where we get 2 Na+ions and 2 Cl- ions(and 1Ba(2+) and (SO4)2-) from one molecule of the compounds seperately which then 'supposedly' form NaCl.
 
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simphys said:
(a): I was wondering what the reason 'd be not to write Na2Cl2 instead of 2NaCl?
my possible explanation, because the ionic compounds dissociate in water(aq solution) where we get 2
Sodium Chloride is not any single molecule. The compound is sodium cations and chloride anions, ratio one-to-one. ONE such unit we symbolize NaCl. Two such units we can show as 2NaCl. If you try to say, Na2Cl2 this suggests you are saying The unit is like a molecule having two of each ion, which it is not.
 
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The key word in the question is BALANCE - your task is to work out how many of each compound there should be in the final balanced equation. It's NOT a typo in the question, it is an unbalanced equation for you to make balanced.

So your answer is correct.

The advice I always gave when lecturing was
Read the question
Read the question again
Answer the question that was asked
I've marked lots of exam papers where the student has not answered what I asked, but what they thought I had asked. Hence the read it again. I used to give students a list of things to do in an exam to get more marks without knowing anything extra, ie clues to what we looked for when marking any question.
 
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DrJohn said:
It's NOT a typo in the question, it is an unbalanced equation for you to make balanced.

Because of 2HCl on the left it doesn't look like a skeletal equation waiting to be balanced.
 
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DrJohn said:
The key word in the question is BALANCE - your task is to work out how many of each compound there should be in the final balanced equation. It's NOT a typo in the question, it is an unbalanced equation for you to make balanced.
Nobody has said it was a typo in the question, it's clearly a typo in the ANSWER.
 
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