First calculate the Molarity of the final solution :
C₁ = 6.0 M
V₁ = 25 mL
C₂ = ?
V₂ = 1.75 * 1000 = 1750 mL
C₁ * V₁ = C₂ * V₂
6.0 * 25 = C₂ * 1750
150 = C₂ * 1750
C₂ = 150 / 1750
C₂ = 0.08571 M
Therefore:
pH = - log [C₂]
pH = - log [ 0.08571 ]
pH = 1.0669
hope this helps!
