6.6 The Electrical Properties of Condensed Phases Questions
Questions :
When cold enough molecular compounds are solid. The following are molecular compounds at room
temperature.
1. CO2(g); 2. wax(s); 3. sugar(s); 4. HCl(g).
Which of these statements is false?
a) Only one of the above does not dissolve in water.
b) HCl(g) dissolves in water to give an ionic solution.
c) Sugar dissolves to give a non-ionic solution.
d) All four substances have low melting points.
e) Since none of them are ionic solids, none of them form aqueous solution that conducts an
electric current.
2. What can you say about the following properties of ionic solids, as NaCl?
a) melting an boiling points
b) Electrical and thermal conductivity
c) Formation of crystals
3. Which is FALSE about NaCl?
a) At room temperature, it is made of NaCl(s) molecules.
b) At room temperature, it conducts electricity
c) In the crystalline state, every sodium ion is surrounded by six chloride ions.
d) Above 808°C, it is a liquid that conducts an electric current.
e) NaCl is its empirical formula, not molecular formula
4. Define anion.
5. Define cation.
6. Which of the following is FALSE?
a) Cations that have a charge of 2+ are magnesium, calcium, barium and lead.
b) Anions that have a charge of 2– are sulfate, carbonate, and chromate.
c) The cation that is made of several atoms is ammonium.
d) SO₂³⁻ is the sulfate ion.
e) The dichromate ion is Cr₂O₇²⁻.
7. Which salt is named or written incorrectly?
a) K2Cr2O7 is potassium dichromate.
b) NH4Cl is chloride ammonium. (ammonium chloride)
c) Lead sulfate is PbSO4. (Lead (II) ssulphate)
d) K2CO3 is potassium carbonate.
e) Barium hydroxide is Ba(OH)2.
8. Examples of metallic and network solids respectively are
a) copper and wax.
b) salt and sugar.
c) gold and charcoal.
d) sodium and diamond.
e) mercury and string.
f) gold and sand
Answers :
When cold enough molecular compounds are solid. The following are molecular compounds at room
temperature.
1. CO2(g); 2. wax(s); 3. sugar(s); 4. HCl(g).
Which of these statements is false?
a) Only one of the above does not dissolve in water.
b) HCl(g) dissolves in water to give an ionic solution.
c) Sugar dissolves to give a non-ionic solution.
d) All four substances have low melting points.
e) Since none of them are ionic solids, none of them form aqueous solution that conducts an
electric current.
2. What can you say about the following properties of ionic solids, as NaCl?
a) melting an boiling points Has high melting and boiling points
b) Electrical and thermal conductivity. Does not conduct electricity when solid
Conduct electricity when molten or aqueous
c) Formation of crystals Form clear or white crystals
3. Which is FALSE about NaCl?
a) At room temperature, it is made of NaCl(s) molecules.
b) At room temperature, it conducts electricity
c) In the crystalline state, every sodium ion is surrounded by six chloride ions.
d) Above 808°C, it is a liquid that conducts an electric current.
e) NaCl is its empirical formula, not molecular formula
4. Define anion.
An anion is a negatively charged ion or an atom that has gained electrons
5. Define cation. A cation is a positively charged ion.
6. Which of the following is FALSE?
a) Cations that have a charge of 2+ are magnesium, calcium, barium and lead.
b) Anions that have a charge of 2– are sulfate, carbonate, and chromate.
c) The cation that is made of several atoms is ammonium.
d) SO₂³⁻ is the sulfate ion.
e) The dichromate ion is Cr₂O₇²⁻.
7. Which salt is named or written incorrectly?
a) K2Cr2O7 is potassium dichromate.
b) NH4Cl is chloride ammonium. (ammonium chloride)
c) Lead sulfate is PbSO4. (Lead (II) ssulphate)
d) K2CO3 is potassium carbonate.
e) Barium hydroxide is Ba(OH)2.