1) Use the Acid-Base table to determine the pKa of the weak acid HCN. 2) What...

Question

Question

1) Use the Acid-Base table to determine the pKa of the weak acid HCN.

2) What is the pH of a 0.00412 M solution of HCl?

3) What is the pH of 0.00685 M solution of NaOH?

science chemistry

Answer 1

Answer #1

ans 1

the weak acid HCN, K_a= 6.0x10^-¹⁰,

pK_a = -log Ka = 9.22.

ans 2

pH = -log [H+] = -log (0.00412)

pH=2.39

ans 3

pOH = -log [OH-] = -log (0.00685)

pOH=2.16

pH + pOH = 14

pH = 14-pOH = 14-2.16

pH = 11.8

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Answer 2

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