Why is ph at the equivalence point larger than 7 when you titrate a weak acid with a strong base?

The equilibrium is shifted to the formation of OH⁻.

Explanation:

AH + OH⁻  ⇄  A⁻ + H₂O

At the equivalence point, the acid AH has entirely been converted to A⁻, which is its conjugated base. This causes the equilibrium to shif to consume the excess of A⁻, which leads to production of OH⁻. This is why, at the equivalence point, the pH is larger than 7.