Question

When the angle of contact between a solid and a liquid is 90°, then *
2 points
(a) Cohesive force > Adhesive force
(b) Cohesive force < Adhesive force
(c) Cohesive force = Adhesive force
(d) Cohesive force >> Adhesive force​

Answer 1

Angle of contact equal to 90 degree is not possible, because in that case cohesive forces( inter molecular forces in liquid) and adhesive forces( forces between molecules of solids and liquids) will be equal. Inter molecular forces in liquids depends on inter molecular potential function .