Hi,
I've been reading a bit about quicklime.
When acids and alkalines react with another substance is the idea that the net result becomes ph neutral?
Also the reaction releases a lot of energy. Is this the energy that has gone into creating them?
PS
I'm just a curious by nature :-)
I've been reading a bit about quicklime.
When acids and alkalines react with another substance is the idea that the net result becomes ph neutral?
Also the reaction releases a lot of energy. Is this the energy that has gone into creating them?
PS
I'm just a curious by nature :-)
-
yes and no
yes if the acid and base each have the same difference from the pH of 7 and the same concentration. e.g. the acid has a pH of 5 and the base has a pH of 9. Then it would be neutralised.
No because they can be different concentrations, pH's, which would mean that that if they are a pH of 5 and 9, and the conc of the acid is 1M L^-1 and the base 0.5M L^-1. or the same conc of 1M L^-1 but a pH of 3 and of 9 for the acid and base.
So it depends on the reaction
The reaction is exothermic, which means that it gives off heat. The heat given off is due to the breaking of bonds and then joining of new bonds
yes if the acid and base each have the same difference from the pH of 7 and the same concentration. e.g. the acid has a pH of 5 and the base has a pH of 9. Then it would be neutralised.
No because they can be different concentrations, pH's, which would mean that that if they are a pH of 5 and 9, and the conc of the acid is 1M L^-1 and the base 0.5M L^-1. or the same conc of 1M L^-1 but a pH of 3 and of 9 for the acid and base.
So it depends on the reaction
The reaction is exothermic, which means that it gives off heat. The heat given off is due to the breaking of bonds and then joining of new bonds
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Yes, when acids and alkalis mix with each other, the substances are neutralised. The act of neutralisation is number 7 on a pH scale (neutral)
Also, the reaction does create a lot of energy because the act of neutralising is very complex which causes high amounts of energy.
Also, the reaction does create a lot of energy because the act of neutralising is very complex which causes high amounts of energy.
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By pH neutral do you mean pH = 7.00.
The pH at the equivalence point of an acid base reaction depends on what is reacting:
1) If you react like with like - that is a strong base with a strong acid then pH = 7.0 at equivalence
An example of this: NaOH + HCl → NaCl + H2O
If you react a weak base with a weak acid , then pH = 7.00 at equivalence.
An example of this: CH3COOH + NH4OH → CH3COONH4 + H2O
2) If you react a strong acid with a weak base , then pH is well below 7.0 at equivalence - probably ≈4.00. An example of this is HCl + NH4OH → NH4Cl + H2O
3) If you react a strong base with a weak acid, at equivalence the pH is well above 7.00 probably ≈ 8.5 - 9.00. An example of this is NaOH + CH3COOH → CH3COONa + H2O
The pH at the equivalence point of an acid base reaction depends on what is reacting:
1) If you react like with like - that is a strong base with a strong acid then pH = 7.0 at equivalence
An example of this: NaOH + HCl → NaCl + H2O
If you react a weak base with a weak acid , then pH = 7.00 at equivalence.
An example of this: CH3COOH + NH4OH → CH3COONH4 + H2O
2) If you react a strong acid with a weak base , then pH is well below 7.0 at equivalence - probably ≈4.00. An example of this is HCl + NH4OH → NH4Cl + H2O
3) If you react a strong base with a weak acid, at equivalence the pH is well above 7.00 probably ≈ 8.5 - 9.00. An example of this is NaOH + CH3COOH → CH3COONa + H2O
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it is not necessary that the reaction of acid and base will lead to the ph neutral because it depends on the strength and weakness of either acid or base. if there is reaction between strong acid and strong base then only it gives neutral ph i.e 7 but in case of strong acid ph is less than 7 and in case of weak acid and strong base ph is greater than 7.