Question

In: Chemistry

For 510.0 mL of a buffer solution that is 0.170 M in CH 3 CH 2...

For 510.0 mL of a buffer solution that is 0.170 M in CH 3 CH 2 NH 2 and 0.150 M in CH 3 CH 2 NH 3 Cl , calculate the initial pH and the final pH after adding 0.010 mol of HCl . Express your answers using two decimal places separated by a comma.

Solutions

Expert Solution

pKb of ethylamine = 3.19

According to the Hinderson Hasselbalch equation :

pOH = pKb + log [CH3CH2NH3Cl/CH3CH2NH2]

       = 3.19 + log [0.15/0.17]

         = 3.14

Initial pH of the solution = 14-pOH = 14-3.19 = 10.81

--------------------------------------------------

when HCl is added, it will react with ethyl amine to convert it to ethyl ammonium chloride

moles of acid added = moles of ethyl ammonium chloride formed. This amount has to be added to ethyl ammonium chloride intially present. same has to be substracted from ethyl amine intitally present

moles of ethyl amine initially present = 0.17 M * 0.510 L = 0.0867 moles

Moles of ethylammonium chloride present = 0.15 M * 0.510 L = 0.0765 moles

Moles of HCl added = 0.01 moles

Moles of ethylamine present after adding HCl = 0.0867 moles - 0.01 = 0.0767 moles

Moles of ethylammoniumchloride present after adding HCl = 0.0765 moles + 0.01 = 0.0865

pOH = pKb + log [CH3CH2NH3Cl/CH3CH2NH2]

       = 3.19 + log [0.0865/0.0767] = 3.24

pH of the solution = 14-pOH = 14-3.24 = 10.76

queen_honey_blossom answered 1 year ago
Next > < Previous

Related Solutions

A 360.0 −mL buffer solution is 0.170 M in HF and 0.170 M in NaF. A)...
A 360.0 −mL buffer solution is 0.170 M in HF and 0.170 M in NaF. A) What mass of NaOH could this buffer neutralize before the pH rises above 4.00? B) If the same volume of the buffer was 0.360 M in HF and 0.360 M in NaF, what mass of NaOH could be handled before the pH rises above 4.00? I keep getting 1.8 g and 3.5 g, which is wrong.
A 340.0 −mL buffer solution is 0.170 M in HF and 0.170 M in NaF. Part...
A 340.0 −mL buffer solution is 0.170 M in HF and 0.170 M in NaF. Part A What mass of NaOH could this buffer neutralize before the pH rises above 4.00? Express your answer using two significant figures. m =   g   Part B If the same volume of the buffer was 0.350 M in HF and 0.350 M in NaF, what mass of NaOH could be handled before the pH rises above 4.00? Express your answer using two significant figures.
A 350.0 −mL buffer solution is 0.170 M in HFand 0.170 M in NaF. A) What...
A 350.0 −mL buffer solution is 0.170 M in HFand 0.170 M in NaF. A) What mass of NaOH could this buffer neutralize before the pHrises above 4.00? B) If the same volume of the buffer was 0.360 M in HF and 0.360 M in NaF, what mass of NaOH could be handled before the pH rises above 4.00?
A 2.00*10^3 mL buffer solution is 0.500 M in H3PO4 and 0.600 M in NaH2PO4. The...
A 2.00*10^3 mL buffer solution is 0.500 M in H3PO4 and 0.600 M in NaH2PO4. The Ka of H3PO4 is 7.5*10^-3. a) What is the initial PH of the buffer solution? b) What is the pH after the addition of 2.00g of LiOH?
For 260.0 mL of a buffer solution that is 0.2869 M in CH3CH2NH2 and 0.2669 M...
For 260.0 mL of a buffer solution that is 0.2869 M in CH3CH2NH2 and 0.2669 M in CH3CH2NH3Cl, calculate the initial pH and the final pH after adding 0.0200 mol of NaOH(Kb=5.6⋅10−4).
For 220.0 mL of a buffer solution that is 0.2869 M in CH3CH2NH2 and 0.2624 M...
For 220.0 mL of a buffer solution that is 0.2869 M in CH3CH2NH2 and 0.2624 M in CH3CH2NH3Cl, calculate the initial pH and the final pH after adding 0.0200 mol of NaOH(Kb=5.6⋅10−4).
For 220.0 mL of a buffer solution that is 0.3028 M in CH3CH2NH2 and 0.2783 M...
For 220.0 mL of a buffer solution that is 0.3028 M in CH3CH2NH2 and 0.2783 M in CH3CH2NH3Cl, calculate the initial pH and the final pH after adding 0.0100 mol of NaOH(Kb=5.6⋅10−4).
For 200.0 mL of a buffer solution that is 0.2975 M in CH3CH2NH2 and 0.2730 M...
For 200.0 mL of a buffer solution that is 0.2975 M in CH3CH2NH2 and 0.2730 M in CH3CH2NH3Cl, calculate the initial pH and the final pH after adding 0.0100 mol of NaOH(Kb=6.46⋅10−4).
If 100.mL of 0.035 M HCl solution is added to 220.mL of a buffer solution which...
If 100.mL of 0.035 M HCl solution is added to 220.mL of a buffer solution which is 0.20M in NH3 and 0.18M in NH4Cl, what will be the pH of the new solution? The Kb of NH3 is 1.8x10^-5. Please explain how the answer was obtained. Thank you!
11 mL of 0.0100 M HCl are added to 25.0 mL of a buffer solution that...
11 mL of 0.0100 M HCl are added to 25.0 mL of a buffer solution that is 0.010 M HC2H3O2 and 0.08 M C2H3O2-.  What is the pH of the resulting solution?
ADVERTISEMENT
Subjects
ADVERTISEMENT
Latest Questions
ADVERTISEMENT