Question

1)

A buffer can be prepared by mixing two solutions. Determine if each of the following mixtures will result in a buffer solution or not.  

1) Mixing 100.0 mL of 0.1 M HCl with 100.0 mL of 0.1 M NaOH                              [ Select ]                       ["No, it will not result in a buffer solution.", "Yes, it will result in a buffer solution."]      

2) Mixing 100.0 mL of 0.1 M CH₃COOH with 100.0 mL of 0.05 M mol CH₃COONa                              [ Select ]                       ["Yes, it will result in a buffer solution.", "No, it will not result in a buffer solution."]      

3) Mixing 100.0 mL of 0.1 M NH₃ with 100.0 mL of 0.1 M NH₄Cl                              [ Select ]                       ["No, it will not result in a buffer solution.", "Yes, it will result in a buffer solution."]      

4) Mixing 100.0 mL of 0.1 M NH₃ with 100.0 mL of 0.05 M HNO₃                              [ Select ]                       ["No, it will not result in a buffer solution.", "Yes, it will result in a buffer solution."]      

5) Mixing 100.0 mL of 0.1 M NH₃ with 100.0 mL of 0.1 M HNO₃                              [ Select ]                       ["No, it will not result in a buffer solution.", "Yes, it will result in a buffer solution."]      

2) A 1.0 L solution initially contains 0.2 M CH₃COOH. Approximate the number of moles of CH₃COOH and CH₃COO⁻ in the solution after 0.1 mol of solid NaOH is added, and calculate the pH of the resulting solution. K_a of CH₃COOH is 1.8 $LaTeX: \times$ ×10⁻⁵.

1) The number of moles of CH₃COOH present is                            [ Select ]                       ["0.0", "0.2", "0.1"]         mol.

2) The number of moles of CH₃COO⁻ present is                            [ Select ]                       ["0.1", "0.0", "0.2"]         mol.

3) The pH of the resulting solution is                            [ Select ]                       ["4.44", "4.74", "5.05"]         .

Answer 1

for a solution to behave us a buffer, a solution of weak and an its or salt on a weak base and its salt are required let us check each option and 1 100mla Hu MaoH are strong aids & bases Hence ita not behave as buffer. 2) CHg LooH is a weak and & CH3 loona is its salt. Hence, it shall behave as a buffer. 3) NHg is a weak base (pkb = 1.8x10-5) and its sult is whad. Hence, it shall behave as a buffer.. 4) NHg is a weak ball and HNO is a strong aid. But they are not related Hence it shall not behave as buffer. 5) gt has same answer as 9. 2 when o.1 mol Nault is added, the following reaction occurs CH 3100H + NaOH - CH3100 Na + H₂O a) No of moles of this cool (0.21.011) = 0.1 moles (Aus) b) No of moles of Ut3 won = moles of NaOH = 0.1 moles (Ang) () PH can be cal weated using Henderssen equation as solution contains Ut3 10 oH & ut, coona pH = pka + log [ut, coona] [uts LooH) OY; PH : - logio (18x10-5) = 4.74. Mus) Hope it helps