Phase Changes and Heat Transfer Quiz

The heat of vaporization of diethyl ether is 351 J/g. How much heat is required to vaporize 1 kg of diethyl ether?

• 3.51 x 10^3 J

• 35.1 J

• 1 x 10^3 J

• 0.351 J

• 3.51 x 10^5 J

Which of the following substances has the highest melting point?

• NaCl

• NO₂

• CO₂

• CH₄

• NH₃

Krypton has a higher melting point than argon because of its:

• hydrogen bonding

• stronger dispersion forces

• permanent dipole moment

• ionic bonds

• greater ionization energy

Which of the following substances exists as a metallic solid?

• KCl

• PH₃

• Ca(NO₃)₂

• Mg

• NO₂

If a compound consists of two types of atoms, A and B, which crystallizes in a face-centered cubic unit cell with A atoms at the faces and B atoms at the corners, what is the formula of the compound?

• AB

• AB₂

• A₂B

• AB₃

• A₃B

What is the name given to a solution that contains the maximum amount of solute that will dissolve in a solvent at a specific temperature?

• saturated

• unsaturated

• solvent

• solute

• supersaturated

According to Henry’s Law, as the pressure of a gas over a solution increases, the solubility of the gas in the solution

• remains unchanged

• decreases

• increases

• cannot be determined

• none of the above

If the solubility of oxygen gas in water at 25°C is 0.0010 mol/L with an oxygen gas pressure of 0.77 atm, what is the solubility of oxygen gas in water (at 25°C) if the oxygen gas pressure is 1.25 atm?

• 0.25 mol/L

• 0.0010 mol/L

• 616 mol/L

• 0.0016 mol/L

• 0.080 mol/L

Potassium fluoride is used for frosting glass. Calculate the molarity of a solution prepared by dissolving 78.6 g of KF in enough water to produce 225 mL of solution.

• 0.304 M

• 0.349 M

• 1.35 M

• 3.29 M

• 6.01 M

What is the boiling point of a solution resulting from dissolving 0.150 moles of sugar (a non-volatile molecular solid) in 150 g of water? (The normal boiling point of water is 100°C, and Kb for water is 0.512 °C/m).

• 0.512°C

• 100.512°C

• 0.000512°C

• 100°C

• 99.488°C