Question

need all FOUR please!! please! provided Ka values if needed

A buffer solution is made that is 0.451 M in H, S and 0.451 M in NaHS. If K for H, Sis 1.00 x 10-7, what is the pH of the buffer solution? pH= Write the net ionic equation for the reaction that occurs when 0.105 mol NaOH is added to 1.00 L of the buffer solution (Use the lowest possible coefficients. Omit states of matter.) Submit Answer Retry Entire Group 2 more group attempts remaining

Answer 1

Q1. 0.451 M H₂S and 0.451 M in NaHS

pH = 7.00

net ionic equation : H₂S + OH^-$\rightarrow$ HS^- + H₂O

Q2. 0.454 M in HNO₂ and 0.454 M in KNO₂

pH = 3.35

net ionic equation : NO₂^- + H₃O⁺$\rightarrow$ HNO₂ + H₂O

Q3. 0.451 M in HCN and 0.451 M in NaCN

The addition of 0.01 mol of OH^- to 1.0 L of this buffer would cause the pH to increase.

The capacity of this buffer for added OH^- could be increased by the addition of 0.169 mol HCN.

Q4. The pK_a value for CH₃COOH is 4.74. Would a buffer prepared from CH₃COOH and CH₃COONa with a pH of 2.74 be considered to be an effective buffer? : No

A buffer in which the mole ratio of CH₃COONa to CH₃COOH is 0.62 has a pH of 4.53. Would this buffer solution have a greater capacity for added acid (H₃O⁺) or added base (OH^-)? : added base (OH^-)