Question

A buffer solution with a pH of 12.05 consists of Na3PO4 and Na2HPO4. The volume of...

A buffer solution with a pH of 12.05 consists of Na3PO4 and Na2HPO4. The volume of solution is 200.0 mL. The concentration of Na3PO4 is 0.370 M.

What mass of Na3PO4 is required to change the pH to 12.30?

Ka = 3.6 × 10-13

_____ g

Science   Chemistry   
0 0
Add a commentTranscribed image text
Next >

Homework Answers

Answer #1

Ka = 3.6 × 10-13

pKa = -log (3.6 × 10-13)

      = 12.44

pH = pKa + log [salt / acid]

12.05 = 12.44 + log [Na3PO4 / Na2HPO4]

[Na3PO4 / Na2HPO4] = 0.4074

0.200 x 0.370 / Na2HPO4 = 0.4074

Na2HPO4 = 0.1816

moles of Na2HPO4 = 0.1816

pH = pKa + log [salt / acid]

12.30 = 12.44 + log [Na3PO4 / Na2HPO4]

[Na3PO4 / Na2HPO4] = 0.7244

Na3PO4 / 0.1816 = 0.7244

moles of Na3PO4 = 0.132

mass of Na3PO4 = 0.132 x 163.94 = 21.57 g

mass of Na3PO4 is required = 21.57 g

0 0
Know the answer?
Your Answer:

Post as a guest

Your Name:

What's your source?

Earn Coins

Coins can be redeemed for fabulous gifts.

Log In

Sign Up

Not the answer you're looking for?
Ask your own homework help question
Similar Questions
A buffer solution with a pH of 12.20 consists of Na3PO4 and Na2HPO4. The volume of...
A buffer solution with a pH of 12.20 consists of Na3PO4 and Na2HPO4. The volume of solution is 200.0 mL. If the concentration of Na3PO4 is 0.470 M, what mass of Na2HPO4 is present?
A buffer solution is composed of 1.126 g of kh2po4 and 5.672 g of Na2HPO4 ....
A buffer solution is composed of 1.126 g of kh2po4 and 5.672 g of Na2HPO4 . ( Ka for dihydrogen phosphate ion is 6.2x 10^-8.) a. what is the PH of the buffer solution? pH = What mass of must be added to decrease the buffer solution pH by 0.10 unit from the value calculated in part a? Mass = ____ g
A 45.0 mL buffer solution is 0.430 M Na2HPO4 (aq) and 0.330 M KH2PO4 (aq). The...
A 45.0 mL buffer solution is 0.430 M Na2HPO4 (aq) and 0.330 M KH2PO4 (aq). The ka for H2PO4- is 6.2*10-8 a. what is the pH of the buffer solution b. what are the pH and the pH change resulting from the addition of 9.0*10-4 mol of NaOH to the buffer solution c. what are the pH and the pH change resulting from the addition of 9.5*10-4 mol of nitric acid to the initial buffer system d. how many mL...
Show calculation for the assigned buffer. Recall: [acid] + [base] = 0.20 M. Calculate the individual...
Show calculation for the assigned buffer. Recall: [acid] + [base] = 0.20 M. Calculate the individual concentrations needed (mass or volume) for HA and A- based on your assigned buffer and pH. The condition [acid] + [base] = 0.20 M must be satisfied. The final volume of solution is 100.0 mL. Assigned Buffer: sodium dihydrogen phosphate and disodium hydrogen phosphate pH = 7.69 Supplemental Data (I believe Ka is 6.2 x10^-8) Acid Species Ka Molar Mass g/mol Compound Phosphoric density...
A buffer solution is composed of 1.212 g of KH2PO4 and 5.740 g of Na2HPO4. (a)...
A buffer solution is composed of 1.212 g of KH2PO4 and 5.740 g of Na2HPO4. (a) What is the pH of the buffer solution? (b) What mass of KH2PO4 must be added to decrease the buffer solution pH by 0.1 unit from the value calculated in part (a)?
1. A buffer solution contains 0.476 M KH2PO4 and 0.202 M Na2HPO4. Determine the pH change...
1. A buffer solution contains 0.476 M KH2PO4 and 0.202 M Na2HPO4. Determine the pH change when 0.050 mol HClO4 is added to 1.00 L of the buffer. pH change = ______ 2. Determine the pH change when 0.077 mol HClO4 is added to 1.00 L of a buffer solution that is 0.331 M in CH3COOH and 0.304 M in CH3COO-. pH after addition − pH before addition = pH change =_____
a buffer is prepared by mixing 500 ml of 0.2 M Na2HPO4 with 500 ml of...
a buffer is prepared by mixing 500 ml of 0.2 M Na2HPO4 with 500 ml of 0.4 M NaH2PO4. a) what is the pH of this buffer B) if 10ml of 1 M HCL was added to this buffer what change in pH would be observed (ignore any change in volume) c) what would the final pH be if you added the same quantity of acid to 1 l of H2O (pH 7) please show all steps
1. You are instructed to make a buffer solution of pH = 4.5. Assume that the...
1. You are instructed to make a buffer solution of pH = 4.5. Assume that the buffer solution is made by mixing a volume of a 0.100 M acetic acid solution and a 0.100 M sodium acetate solution. Determine the volume (in mL) of acetic acid required to prepare 60.0 mL of your assigned buffer pH. 2. Based on the previous question, calculate the concentration of [HA] in this buffer solution. 3. 20.0 mL of the buffer solution (from above)...
A buffer solution contains 0.233 M ammonium chloride and 0.321 M ammonia. If 0.0188 moles of...
A buffer solution contains 0.233 M ammonium chloride and 0.321 M ammonia. If 0.0188 moles of perchloric acid are added to 150 mL of this buffer, what is the pH of the resulting solution ? (Assume that the volume does not change upon adding perchloric acid) pH = A buffer solution contains 0.338 M NaH2PO4 and 0.394 M Na2HPO4. If 0.0497 moles of perchloric acid are added to 225 mL of this buffer, what is the pH of the resulting...
NH3/NH4 buffer: Mass NH4Cl used 1.3738g volume NaOH used 21.2 ml initial pH (0f the buffer)...
NH3/NH4 buffer: Mass NH4Cl used 1.3738g volume NaOH used 21.2 ml initial pH (0f the buffer) 9.6, pH after 1 drop HCl 9.03, pH after 10 drops HCl 8.91 Dilute NaOH solution Initial pH 10.35 pH :1 drop HCl 10.21, 10 drops HCl 2.85 Acetate buffer (0.500) Mass of CH3COONa * 3H2O 10.935 volume CH#COOH 44.3 ml initial pH 4.89 1.0 ml of NaOH pH 4.93 initial volume 2.2 final volume 16.2 final pH 5.91 Acetate buffer (0.100) Mass of...
ADVERTISEMENT
Need Online Homework Help?

Get Answers For Free
Most questions answered within 1 hours.

Ask a Question
ADVERTISEMENT