Regents Review Gas and Solutions

Which compound is insoluble in water?

• BaSO₄

• CaCrO₄

• KClO₃

• Na₂S

A sample of a gas is contained in a closed rigid cylinder. According to kinetic molecular theory, what occurs when the gas inside the cylinder is heated?

• The number of gas molecules increases

• The number of collisions between gas molecules per unit time decreases

• The average velocity of the gas molecules increases

• The volume of the gas decreases

Which two gas samples contain the same total number of particles?

• 2L CH₄ and 1L CO₂

• 3L He and 2L CO₂

• 2L CH₄ and 5L Ne

• 5L He and 5L Ne

An unsaturated aqueous solution of NH₃ is at 90.0°C in 100 grams of water. According to Reference Table G, how many grams of NH₃ could this unsaturated solution contain?

• 5 g

• 10 g

• 15 g

• 20 g

How many total moles of KNO₃ must be dissolved in water to make 1.5 liters of a 2.0 M solution?

• 0.50 mol

• 2.0 mol

• 3.0 mol

• 1.3 mol

Which statement explains why low temperature and high pressure are required to liquefy chlorine gas?

• Chlorine molecules have weak covalent bonds

• Chlorine molecules have strong covalent bonds

• Chlorine molecules have weak intermolecular forces of attraction

• Chlorine molecules have strong intermolecular forces of attraction

Which ion, when combined with chloride ions (Cl^-), forms an insoluble substance in water?

• Fe²⁺

• Mg²⁺

• Pb²⁺

• Zn²⁺

Molarity is defined as the

• moles of solute per kilogram of solvent

• moles of solute per liter of solution

• mass of a solution

• volume of a solvent

A saturated solution of NaNO₃ is prepared at 60.0°C using 100 grams of water. As this solution is cooled to 10.0°C, NaNO₃ precipitates (settles) out of the solution. The resulting solution is saturated. Approximately how many grams of NaNO₃ settled out of the original solution?

• 46 g

• 61 g

• 85 g

• 126 g

Compared to the freezing point of 1.0 M KCl(aq) at standard pressure, the freezing point of 1.0 M CaCl₂(aq) at standard pressure is:

• lower

• higher

• the same

• beyond the scope of human reasoning