Estimate the critical constants for diphenylmethane using Lydersen’s method; normal boiling point 537.5 K, molecular mass 168.2, structural formula:
Estimate the critical constants for diphenylmethane using Lydersen’s method; normal boiling point 537.5 K, molecular mass 168.2, structural formula:
Group | No. of | Total contribution | ||
ΔT | ΔP | ΔV | ||
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10 | 0.11 | 1.54 | 0.37 |
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2 | 0.022 | 0.308 | 0.072 |
–CH2− | 1 | 0.02 | 0.227 | 0.055 |
Σ0.152 | 2.075 | 0.497 |
Tc=(0.567+0.152−0.1522)537.5=772k
experimental value 767 K,
Pc=(0.34+2.075)2168.2=28.8atm
experimental value 28.2 atm,
Vc=0.04+0.497=0.537m3/kmol