Chemistry Honors

Pre-Lab Worksheet

Q.)Which type of compound usually has higher melting points: ionic compounds or covalent compounds? What is the reason for this difference in melting points?
A.) Ionic compounds have higher melting points than covalent compounds. Its’ caused by the electrostatic attraction in an ionic bond which is very strong hence a lot of heat energy is required to break it down. Whereas covalent bonds, the forces are very weak and is easily broken.
Q.) Do ionic compounds conduct electricity as:
A.) (in regards to being a solid state) No, because even though there are oppositely charged ions in ionic substances, when these are in a solid state, the ions cannot move and thus there is no flow of charge.
A.) (in regards to being a liquid state) Yes, the ions are broken up and are free to carry an electrical current
A.) (in regards to being a Aqueous solution) Yes.
Q.) Do covalent compounds conduct electricity as:
A.) (in regards to being a solid state) Covalent bond usually don't conduct electricity. Because they do not have free electrons.
A.) (in regards to being a liquid state) Covalent bond usually don't conduct electricity. Because they do not have free electrons.
A.) (in regards to being a Aqueous solution) Covalent bond usually don't conduct electricity. Because they do not have free electrons.

Lab Worksheet
Part I

Substance
Melting Point
Substance A
Higher than 300°C
Substance B
200°C
Substance C
Higher than 300°C
Substance D
130°C

Compound
Conduct electricity in a solid state
Conduct electricity in a liquid state