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NaOH + H2SO4

Why does it give
NaOH + H2SO4 = Na2SO4 +2H2O -- when balanced...

and not

NaOH + H2SO4 = NaHSO4 and H2O? - - - - does this not make more sense and no need for balancing?

Is it because the H2SO4 is a strong dibasic acid and will fully dissociate...ie. 2H+ and SO4 2-? and thus, not H+ and HSO4- ?
Original post by revisionlad
Why does it give
NaOH + H2SO4 = Na2SO4 +2H2O -- when balanced...

and not

NaOH + H2SO4 = NaHSO4 and H2O? - - - - does this not make more sense and no need for balancing?

Is it because the H2SO4 is a strong dibasic acid and will fully dissociate...ie. 2H+ and SO4 2-? and thus, not H+ and HSO4- ?


because it's an acid + alkali, which is neutralization and gives out water and salt (no clue what the other one is)

the one you've said gives us alkali, which is wrong.

You're saying that alkali + acid --> alkali + water. This is not neutralization.
Original post by RickHendricks
because it's an acid + alkali, which is neutralization and gives out water and salt (no clue what the other one is)

the one you've said gives us alkali, which is wrong.

You're saying that alkali + acid --> alkali + water. This is not neutralization.


Thanks for the reply,

Which one is alkali?
The first one is a neutralisation reaction because it gives sodium sulfate (neutral salt)

But the second one gives Sodium hydrogen sulfate, which I think is an acidic salt when dissolved in water - - HSO4- + H2O = H3O+ & SO4 2-
Original post by revisionlad
Thanks for the reply,

Which one is alkali?
The first one is a neutralisation reaction because it gives sodium sulfate (neutral salt)

But the second one gives Sodium hydrogen sulfate, which I think is an acidic salt when dissolved in water - - HSO4- + H2O = H3O+ & SO4 2-


but not when it comes in this reaction.

In this reaction it's just a base.
Original post by RickHendricks
but not when it comes in this reaction.

In this reaction it's just a base.


sorry, but can you clarify what is the base you are inferring to?

thanks.
Reply 5
Original post by revisionlad
Why does it give
NaOH + H2SO4 = Na2SO4 +2H2O -- when balanced...

and not

NaOH + H2SO4 = NaHSO4 and H2O? - - - - does this not make more sense and no need for balancing?

Is it because the H2SO4 is a strong dibasic acid and will fully dissociate...ie. 2H+ and SO4 2-? and thus, not H+ and HSO4- ?


Yes, you're right, H2SO4 is a strong acid and therefore it fully dissociates. If it were a weak diprotic/dibasic acid, such as ethanedioic acid (COOH-COOH), with a strong base such as NaOH, you would firstly get COOH-COO-Na+ + H2O. Then, if you added more NaOH, you would get COO-Na+-COO-Na+ + H2O. This is because ethanedioic acid does not fully dissociate.

Reaction 1: COOH-COOH + NaOH ==> COOH-COO-Na+ + H2O
Reaction 2: COOH-COO-Na+ + NaOH ==> COO-Na+-COO-Na+ + H2O.
Original post by Jpw1097
Yes, you're right, H2SO4 is a strong acid and therefore it fully dissociates. If it were a weak diprotic/dibasic acid, such as ethanedioic acid (COOH-COOH), with a strong base such as NaOH, you would firstly get COOH-COO-Na+ + H2O. Then, if you added more NaOH, you would get COO-Na+-COO-Na+ + H2O. This is because ethanedioic acid does not fully dissociate.

Reaction 1: COOH-COOH + NaOH ==> COOH-COO-Na+ + H2O
Reaction 2: COOH-COO-Na+ + NaOH ==> COO-Na+-COO-Na+ + H2O.


Hi! That makes a lot more sense! Thank you so much.

Also, would you mind answering another q I posted earlier about equilirium...ill post it here too..


"I was wondering what the difference is between the Position of Equilibrium and the Equilibrium constant (Kc) is.

For example, I understand that Kc value is only influenced by temperature, but then what does this signify? Because if I increase the temperature of an endothermic (forward) reaction, Kc would increase, but also the posiition of Equilirbium will shift to the right (in the endothermic direction) hence I obtain more yield of products - Le Chatlier's principle right?

But, did i obtain more product yield because my Kc value increased or because of position of Equilibrium shifting to the right (Le Chat)? -- so far I believe it's because of Le Chats principle, but then what influence does Kc have, if any?"

Thanks again!
Original post by revisionlad
Why does it give
2NaOH + H2SO4 = Na2SO4 +2H2O -- when balanced...

and not

NaOH + H2SO4 = NaHSO4 and H2O? - - - - does this not make more sense and no need for balancing?

Is it because the H2SO4 is a strong dibasic acid and will fully dissociate...ie. 2H+ and SO4 2-? and thus, not H+ and HSO4- ?


Both of these reactions are correct.

The extent of the reaction just depends on the moles of sodium hydroxide added.

equal moles of sodium hydroxide and sulfuric acid
NaOH + H2SO4 --> NaHSO4 and H2O

excess moles of sodium hydroxide
2NaOH + H2SO4 --> Na2SO4 +2H2O

The dissociation of the acid is not a factor.

In any case, only the first dissociation is 100%, the second is less than 10%.

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