Pulverised coal passing through 200 mesh screen has a diameter of 0.074 mm (74 micron). The same passing through 50 mesh screen will have a dia of __________ mm.
7. The heats of vaporisation of CS2, C2H5OH &H2O are 26.8, 38.6 & 40.6 KJ/kg mole respectively. The order of decreasing inter-molecular forces in these liquids is