A buffer solution is prepared in which the concentration of `NH_(3)` is 0.30M and the concentration of `NH_(4)^(+)` is 0.20M . If the equilibrium constant `k_(b)` for `NH_(3)` equals `1.8xx10^(-3)` what is the `pH` of this solution?A. 11.72B. 8.73C. 9.08D. 9.43.

A buffer solution is prepared in which the concentration of `NH_(3)` i

1.	A buffer solution is prepared in which the concentration of `NH_(3)` is 0.30M and the concentration of `NH_(4)^(+)` is 0.20M . If the equilibrium constant `k_(b)` for `NH_(3)` equals `1.8xx10^(-3)` what is the `pH` of this solution?A. 11.72B. 8.73C. 9.08D. 9.43.
Answer» Correct Answer - D `[NH_(3)]=0.3M,[NH_(4)^(+)]=0.2M` `k_(b)=1.8xx10^(-5)` `NH_(3)+H_(2)OhArrNH_(4)^(+)+OH^(-)` `K_(b)=([NH_(4)^(+)][OH^(-)])/([NH_(3)])rArr[OH^(-)]=(k_(b)xx[NH_(3)])/([NH_(4)^(+)])` `[OH^(-)]=(1.8xx10^(-5)xx0.3)/(0.2)=2.7xx10^(-5)` `pOH=-"log"[OH^(-)]=-"log"(2.7xx10^(-5))` `=5-"log"2.7=5-0.43=4.57` `therefore pH=14-pOH=14-4.57=9.43`

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A buffer solution is prepared in which the concentration of `NH_(3)` is 0.30M and the concentration of `NH_(4)^(+)` is 0.20M . If the equilibrium constant `k_(b)` for `NH_(3)` equals `1.8xx10^(-3)` what is the `pH` of this solution?A. 11.72B. 8.73C. 9.08D. 9.43.

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