A mixture of toluene and benzene forms a nearly ideal solution. Assume `P_B^@ and P_T^@` to be the vapor pressures of pure benzene and toluene, respectively. The slope of the line obtained by plotting the total vapor pressure to the mole fraction of benzene is :

Options

A. `P_(B)^(@) - P_(T)^(@)`
B. `P_(T)^(@) -P_(B)^(@)`
C. `P_(B)^(@) +P_(T)^(@)`
D. `(P_(B)^(@) +P_(T)^(@))//2`

Answer

A

Explanation

` P_("total") =chi_B (P_(B)^(0)) + chi_(T) (P_(T)^(0)) = chi_(B)^(0) ) + (1- chi_(B))(P_(T)^(0))`
comparing it withc y= mx + c