Question

If the slope of line B is $-0.10Lmo{l}^{-1}$, what is the relationship between vander Waal's constants 'a' and 'b'?

• A. a=$(b+\frac{1}{10})\frac{1}{24.6}atm{L}^{2}mo{l}^{-2}$
• B. b=$(b-\frac{1}{10})\times 24.6Lmo{l}^{-1}$
• C. $b=\frac{a}{24.6Latm/mol}-0.10L/mol$
• D. b=$(a+\frac{1}{10})\times 24.6Lmo{l}^{-1}$

Answer 1

The correct option is C $b=\frac{a}{24.6Latm/mol}-0.10L/mol$

Whe Z is ploted vs $\frac{1}{V_m}$, the slope is -0.10 L/mol. It is equal to
$(b-\frac{a}{RT})$
$(b-\frac{a}{RT})=-0.10L/mol$
$b=\frac{a}{RT}-0.10L/mol$
$b=\frac{a}{0.08206Latm/mol/K\times 300K}-0.10L/mol$
$b=\frac{a}{24.6Latm/mol}-0.10L/mol$