Question

if the only force of interaction is the dispersion force, you would expect the molecule to be
(a) a. high boiling
(b) b. low boiling
(c) c. no dependence
(d) d. boil at 100 °c
question 9
0.5 pts
the force of interaction which is always present in all molecules is
(a) a. ion - dipole
(b) b. dipole - dipole
(c) c. london forces
(d) d. h - bonding
question 10
1 pts
which of the following solvents will have ion dipole interactions with na+?
(a) a. benzene(c6h6)
(b) b. carbon tetrachloride (ccl4)
(c) c. chloroform (chcl3)
(d) d. cyclohexane(c6h12)

Explanation:

1. Dispersion forces are the weakest intermolecular forces. Molecules held together only by dispersion forces have low boiling - points as less energy is needed to separate the molecules.
2. London forces (dispersion forces) are always present in all molecules due to the temporary dipoles formed by the motion of electrons.
3. Ion - dipole interactions occur between an ion and a polar molecule. Chloroform ($CHCl_3$) is a polar molecule and can have ion - dipole interactions with $Na^+$. Benzene ($C_6H_6$), carbon tetrachloride ($CCl_4$) and cyclohexane ($C_6H_{12}$) are non - polar molecules.

Answer:

1. b. low boiling
2. c. London forces
3. c. chloroform ($CHCl_3$)