Enthalpy of vaporization is also known as latent heat of vaporization or heat of evaporation.
On increasing temperature it increases.
It decreases on increasing pressure, since at high pressure molecules collide more frequently and have high energy, so at high pressure less energy is required to change the phase of the substance.
Viscosity decreases as the temperature rises because at high temperature molecules have kinetic energy and can overcome inter-molecule forceswces