# Problem: A 1.00 L buffer solution is 0.250 M in HF and 0.250 M in NaF. Calculate the pH of the solution after the addition of 100.0 mL of 1.00 M HCl. The Ka for HF is 3.5 × 10-4. A) 3.09B) 4.11C) 3.82D) 3.46E) 2.78

###### FREE Expert Solution
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###### FREE Expert Solution

We’re being asked to calculate the pH of a buffer solution after the addition of HCl solution. The buffer solution is made up of 0.250 M HF and 0.250 M NaF.

Since the solution is a buffer, we know that HF is a weak acid and NaF is the conjugate base. HCl will react with the base NaF.

Reaction:         NaF(aq) + HCl(aq) → HF(aq) + NaCl(aq)

We will calculate the pH of the solution using the following steps:

81% (130 ratings)
###### Problem Details

A 1.00 L buffer solution is 0.250 M in HF and 0.250 M in NaF. Calculate the pH of the solution after the addition of 100.0 mL of 1.00 M HCl. The Ka for HF is 3.5 × 10-4

A) 3.09

B) 4.11

C) 3.82

D) 3.46

E) 2.78

What scientific concept do you need to know in order to solve this problem?

Our tutors have indicated that to solve this problem you will need to apply the Weak Base Strong Acid Titrations concept. You can view video lessons to learn Weak Base Strong Acid Titrations. Or if you need more Weak Base Strong Acid Titrations practice, you can also practice Weak Base Strong Acid Titrations practice problems.

What is the difficulty of this problem?

Our tutors rated the difficulty ofA 1.00 L buffer solution is 0.250 M in HF and 0.250 M in NaF...as high difficulty.

How long does this problem take to solve?

Our expert Chemistry tutor, Jules took 4 minutes and 25 seconds to solve this problem. You can follow their steps in the video explanation above.

What professor is this problem relevant for?

Based on our data, we think this problem is relevant for Professor Hashim's class at UCF.