a solution of sodium hydroxide is standardized against potassium hydrogen phthalate (KHP, formula weight 204.2 g/mol). From the following data, calculate the molarity of the NaOH solution: mass of KHP 1.404 g; buret reading before titration 0.13 mL; buret reading after titration 47.07 mL. Answer in unit of M
I worked one like this earlier. The numbers are different but I think that is all.
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To calculate the molarity of the NaOH solution, you need to first determine the number of moles of KHP used in the titration. Then, using the stoichiometry of the reaction, you can determine the number of moles of NaOH.
1. Calculate the number of moles of KHP:
Number of moles = mass / molar mass
Given that the mass of KHP used is 1.404 g and the molar mass of KHP is 204.2 g/mol, we can calculate the number of moles:
Number of moles = 1.404 g / 204.2 g/mol
2. Determine the stoichiometry of the reaction:
The balanced chemical equation for the reaction between NaOH and KHP is:
NaOH + KHP → NaKP + H2O
From the balanced equation, you can see that the stoichiometric ratio between NaOH and KHP is 1:1. This means that 1 mole of NaOH reacts with 1 mole of KHP.
3. Calculate the number of moles of NaOH:
Since the stoichiometric ratio is 1:1, the number of moles of NaOH is equal to the number of moles of KHP.
4. Calculate the volume of NaOH solution:
Buret reading = volume of NaOH solution used in the titration
Buret reading = final volume - initial volume
Buret reading = 47.07 mL - 0.13 mL
5. Convert the volume of NaOH solution to liters:
Volume (L) = volume (mL) / 1000
6. Calculate the molarity of the NaOH solution:
Molarity (M) = moles / volume (L)
Now, let's calculate the molarity of the NaOH solution:
1. Number of moles of KHP = 1.404 g / 204.2 g/mol
2. Number of moles of NaOH = Number of moles of KHP
3. Volume of NaOH solution = (47.07 mL - 0.13 mL) / 1000
4. Molarity of NaOH solution = Number of moles of NaOH / Volume of NaOH solution
Plug in the calculated values and solve for the molarity of the NaOH solution, expressing the answer in units of M (mol/L).