The concentration of OH⁻ is first converted to pOH bu using followinf formula,
pOH = -log [OH⁻]
Putting value,
pOH = -log (0.006)
pOH = 2.221
As we know,
pH + pOH = 14
Solving for pH,
pH = 14 - pOH
Putting value of pOH,
pH = 14 - 2.221
pH = 11.779
Result:
Option-1 is the correct answer.
