Question

2A) An engineer is using reverse osmosis (“RO”) to desalinate a tank of contaminated water that has a concentration of 0.269 M CaCl2 (strong electrolyte) at 21.00°C to form deionized water. Given that 1 atm = 14.7 psi, the pressure he/she needed to apply across the “RO” membrane should be:

(a) 422 psi​ (b) 286 psi​ (c) 179 psi​ (d) 206 psi

2B) An ideal liquid solution was made by mixing 22.5 moles of solvent “A” with 52.2 moles of solvent “B”. The vapor pressures, at a given temperature, of solvent “A” and solvent “B” are 61.8 Torr and 35.8 Torr, respectively. The vapor pressure over this solution is:

(a) 47.1 Torr​(b) 55.3 Torr​(c) 43.6 Torr​(d) 57.4 Torr