Moles of A=0.714mol Moles of B=5.555mol P‌solution ‌=475 torr PA0=280.7 torr PB0= ? Step 1. Mole fractions ‌xA=‌
0.714
0.714+5.555
=‌
0.714
6.269
=0.1138 ‌xB=1−xA=0.8862 Step 2. Raoult's law For an ideal solution: P‌total ‌=PA+PB=xAPA0+xBPB0 We know everything except PB0. So: 475=(0.1138)(280.7)+(0.8862)PB0 Step 3. Solve for PB0 Compute first term: 0.1138×280.7=31.93 Thus ‌475=31.93+0.8862PB0 ‌0.8862PB0=475−31.93=443.07 ‌PB0=‌
