Effects of Intermolecular Forces on Properties of Substances

Liquids can form spherical elastic film to minimize surface area.

What intermolecular forces are responsible for the formation of this film

in water?

• dipole-induced dipole

• H-bonding

• ion-induced dipole

• London dispersion forces

Which among the following is the amount of energy required to stretch

or increase the surface of a liquid by a unit area (ex., 1 cm2)?

• heat of vaporization

• specific heat

• surface tension

• vapour pressure

How is the ability of water molecules to move against gravity referred

to?

• capillary action

• surface tension

• temperature

• viscosity

Tags

NGSS.MS-ESS2-4

Substances like heavy syrup and molasses flow slower than water.

How is the ability of these substances to resist flow called?

• capillary action

• pressure

• surface tension

• viscosity

What is the term that pertains to the pressure exerted by the vapor from

the evaporation of a liquid or solid above a sample of the liquid or solid

in a closed container?

• boiling point

• capillary action

• surface tension

• vapour pressure

What is true about liquids with strong intermolecular forces?

• Vapour pressure is low

• Vapour pressure is high.

• Viscosity tends to be high.

• Viscosity is immeasurable

What happens when the vapour pressure of a liquid becomes equal

to the atmospheric pressure?

• The liquid will boil.

• The vapour will condense.

• Melting of the solid form will start.

• There will be freezing of the liquid.

Tags

NGSS.MS-PS1-4

The atmospheric pressure on top of a mountain is lower than at sea

level. As a consequence, what will happen to the cooking time of an

egg on top of the mountain?

• The egg will cook faster since the boiling temperature will be

  lower.

• The egg will cook at a shorter time since the boiling temperature

  will be higher.

• The egg will cook at a longer time due to a lower boiling

  temperature.

• The egg will cook at a shorter time due to higher boiling

  temperature.

Sodium chloride is completely soluble in water. What is responsible

for its solubility in water?

• Na+ and Cl- ions are favorable sites for H-bonding to form.

• The ions in NaCl participate in ion-induced dipole attractions with

  water.

• The presence of charged ends in NaCl enables dipole-dipole

  interaction with water.

• London dispersion forces in NaCl predominate leading to strong

  dipole interactions with water.

Xenon has a greater atomic weight than neon. Xe has 131.3 amu while

Ne has 20.2 amu. The boiling points are 166.1K and 27.3K, respectively.

How do intermolecular forces account for the difference?

• Dipole- dipole interaction is greater in Xe than Ne so more

  energy is needed to break the bonds.

• H-bonding is greater for substances with higher atomic weight

  so greater energy is needed to change Xe to vapour.

• Atomic weight increases the chance of lesser dispersion forces

  so greater energy is needed to separate Xe atoms to change to

  vapour

• London dispersion forces are greater in substances with

  heavier atomic weight so greater energy is needed to separate

  the atoms of Xe than Ne.