Question

Hey guys, I am having a lot of trouble with my homework. Could you please help? I thumbs up anyone who gives a thorough explanation and shows the work! I really need to understand these concepts!

1) The Ka for HCN is 4.9 ~ 10-10. What is the value of Kb for CN-? 2) Using the data in the table for 0.10 M aqueous species at 25 °C, which conjugate base below is the weakest base? Explain your answer for full credit! Acid ка. НОАс 1.8 x 10-5 HC7H502 6.3 10-5 HNO2 4.5 x 10-4 HF 6.8 x 10-4 3) The Ka for HCN is 4.9 10-10. What is the pH of a 0.068 M aqueous solution of potassium cyanide?

Thanks in advance!

Answer 1

HC / دم CN b car is the conjugate base of non & for Conjugate acid-Base pain we have to use Karky kw loty Ky kw ka 4.9 xlo-lo ky z 0-204 x 10-4 y 2:04 x 10-5 Tu b

so mo gre ates ka Value Means Strong acid other than in list. $ conjugate of stro song acid is weak base So for the compound whose Ka Value is weakest conjugat Base So Maximum Ka I So HF form conjugate Base (F-) Maximum form a 6.8 X10-y weakest

| only Salt is KCN D669 So 3 there so bydrolysis O: 069 D: 068 Occure, CN + H₂O HON at (би 0.08-M 1-4 - 22 kw lea {orocesu 4.340 รา 0.019- 2e =) 20² 0.08-14 4.9 xloro => -> x na Jo .013 x 15-4 1.3% 10 1.14 x 10-3 =(our] pon by Cot) = uxlov pon - 3-logy - 3-oost = 3.944 logiin pl=14-2.544 pn pon