Estimate the mass of KHP (formula: KHC8H4O4) that will require 25mL of 0.10M NaOH to reach the equivalence point in a titration. Give the chemical equiation for the reaction.
2007-02-27 03:37:36 · 3 answers · asked by Anonymous in Science & Mathematics ➔ Chemistry
Since the reaction occurs with a 1:1 stoichiometry between KHP and NaOH, just calculate the moles of NaOH (0.025 L X 0.1 mol/L), and then multiply that by the molar mass of KHP to give you grams of KHP.
You punch the calculator buttons.
2007-02-27 03:42:45 · answer #1 · answered by hcbiochem 7 · 1⤊ 0⤋
Lancenigo di Villorba (TV), Italy
I confirm the HCBIOCHEM's suggest.
You need ONE HALF GRAM.
The reaction involved follows :
HOOC-C6H4-COO-K+(aq) + Na+OH-(aq) <--->
<---> Na+-OOC-C6H4-COO-K+(aq) + H2O(aq)
In this scheme you state that KHP and sodium hydroxide are "mono-valent electrolytes" bother.
By means of some drops of Phenolphtalein's stuff, you stop the titrimetric addiction of sodium hydroxide 0.10 M when you note the appearing of a pinkish hue. This conditions is called "equivalence point", that is you added a mole's number of oxydril's ions similar to hydrogen's one.
In mathematical terms I write
na = Cb * Vb
where na is the mole's number at the equivalence conditions, that is
na = 0.10 * 2.5E-2 = 2.5E-3 mol
Ma = na * MWa = 2.5E-3 * 204 = 0.51 g
I hope this helps you.
2007-02-27 03:55:55 · answer #2 · answered by Zor Prime 7 · 0⤊ 0⤋
KHP + NaOH -> NaKPhthalate + Water
1:1 mole ratio
moles Acid needed equals moles base used for neutralization
.025L*0.10M= .0025 moles KHP
.0025 moles * appx 204grams per mole gives you the answer
2007-02-27 03:44:42 · answer #3 · answered by piercesk1 4 · 0⤊ 0⤋