Question

a and b are Vander Waal's constants for gases. Chlorine is more easily liquefied than ethane because:

• A. a and b for $C{l}_2$ > a and b for $C_2{H}_6$
• B. a and b for $C{l}_2$ < a and b for $C_2{H}_6$
• C. a for $C{l}_2$ > a for $C_2{H}_6$ but b for $C{l}_2$ > b for $C_2{H}_6$
• D. a for $C{l}_2$ > a for $C_2{H}_6$ but b for $C{l}_2$ < b for $C_2{H}_6$

Answer 1

Answer: (D)

a for $C{l}_2$ > a for $C_2{H}_6$ but b for $C{l}_2$ < b for $C_2{H}_6$

Van der waals constant ${}^{\prime }{a}^{\prime }$ is a mixture of inter molecular forces and ${}^{\prime }{b}^{\prime }$ is a measure of molecular size. A greater value of ${}^{\prime }{a}^{\prime }$ and lesser value of ${}^{\prime }{b}^{\prime }$ supports qualification of a given gas. Therefore, chlorine is more easily liquefied than ethane because ${}^{\prime }{a}^{\prime }$ for ${Cl}_2>$ ${}^{\prime }{a}^{\prime }$ for $C_2{H}_6$ but ${}^{\prime }{b}^{\prime }$ for ${Cl}_2>$ ${}^{\prime }{b}^{\prime }$ for $C_2{H}_6$.