What is negative deviation?

What is meant by negative deviation from Raoult's law and how is the sign of Delta_("mix")H related to negative deviation from Raoult's law ?

Under what condition do non-ideal solutions show negative deviations?

Under what condition do non-ideal solutions show negative deviations?

Under what condition do non-ideal solutions show negative deviations?

In a mixture of A and B , components show negative deviation when

In a mixture of A and B components show negative deviation when

In a mixture of A and B, components show negative deviation when