Structure 1.1 Test Review

Which of the following are examples of homogeneous mixtures?

I. Air

II. Steel

III. Aqueous potassium manganate(VII)

• II only

• III only

• I and II only

• I, II, and III

What correctly describes the sublimation of dry ice (carbon dioxide)?

• Exothermic

  CO₂(s) -> CO₂(g)

• Exothermic

  CO₂(s) -> C(g) + O₂(g)

• Endothermic

  CO₂(s) -> CO₂(g)

• Endothermic

  CO₂(s) -> C(g) + O₂(g)

Which of the following methods could be used to obtain solid sodium chloride from a solution of sodium chloride in water?

I. Evaporation

II. Filtration

III. Distillation

• I only

• I and II only

• I and III only

• I, II, and III

Which changes of state are opposite to each other?

• Melting and condensation

• Vaporization and deposition

• Deposition and sublimation

• Sublimation and freezing

Which of the following statements is incorrect?

• Solids and liquids are almost incompressible

• Particles in both solids and liquids are mobile

• Liquids and gasses have no fixed shape

• Particles in solids, liquids, and gases can vibrate

Which elements can be separated from each other by physical methods?

• Oxygen and nitrogen in the air

• Hydrogen and oxygen in water

• Carbon and oxygen in dry ice

• Magnesium and sulfur in magnesium sulfide

Which change in temperature on the Celsius scale is equivalent to the increase in temperature by 20K?

• Decrease by 20^oC

• Increase by 20^oC

• Decrease by 293.15^oC

• Increase by 293.15^oC

In which changes do the particles move further apart?

• W and X

• W and Z

• X and Y

• Y and Z

A sugar cube is dropped into a hot cup of tea.

The tea is not stirred.

Which statement explains why the tea becomes sweet?

• The heated water molecules penetrate the sugar cube.

• The hot tea causes the sugar to melt.

• The sugar cube dissolves and its molecules diffuse.

• The sugar molecules get hot and evaporate.

A liquid is heated until it boils.

Which result shows that the liquid in the test-tube is pure water?

• Condensation forms at the top of the test-tube.

• Steam is produced.

• The thermometer reads 100 °C.

• There is nothing left behind in the test-tube.