Question

1. properties of ionic compounds

a) ____________ melting and boiling points
b) always form ____________
c) conduct ____________ when melted or in solutions
d) ____________ in water and do not dissolve in other organic solvents
e) ____________ and breaks into small pieces easily

1. write the name for the following compounds:

a. nabr c. k₂s
b. mgo d. li₂o

1. what are the ion charges for the following elements?

a. sodium (na) e. chlorine (cl)
b. fluorine (f) f. aluminum (al)
c. nitrogen (n) g. oxygen (o)
d. calcium (ca) h. potassium (k)

1. write the chemical formula for the following compounds:

a. calcium fluoride c. potassium bromide
b. sodium oxide d. aluminum oxide

Explanation:

1. Ionic compounds have strong electrostatic forces between ions, leading to high melting and boiling points. They form crystalline structures. When melted or in solution, ions are free to move, allowing conduction of electricity. They are generally soluble in water (due to ion - dipole interactions) and insoluble in organic solvents. Ionic compounds are brittle as the layers shift and like - charged ions repel.
2. For naming ionic compounds:

• For \(NaBr\): Sodium (metal) and Bromine (non - metal). Drop “ine” from bromine and add “ide” → Sodium bromide.
• For \(MgO\): Magnesium (metal) and Oxygen (non - metal). Drop “ygen” from oxygen and add “ide” → Magnesium oxide.
• For \(K_2S\): Potassium (metal) and Sulfur (non - metal). Drop “ur” from sulfur and add “ide” → Potassium sulfide.
• For \(Li_2O\): Lithium (metal) and Oxygen (non - metal). Drop “ygen” from oxygen and add “ide” → Lithium oxide.

1. Ion charges:

• Sodium (\(Na\)) loses 1 electron → \(Na^+\).
• Fluorine (\(F\)) gains 1 electron → \(F^-\).
• Nitrogen (\(N\)) gains 3 electrons → \(N^{3 - }\).
• Calcium (\(Ca\)) loses 2 electrons → \(Ca^{2+}\).
• Chlorine (\(Cl\)) gains 1 electron → \(Cl^-\).
• Aluminum (\(Al\)) loses 3 electrons → \(Al^{3+}\).
• Oxygen (\(O\)) gains 2 electrons → \(O^{2 - }\).
• Potassium (\(K\)) loses 1 electron → \(K^+\).

1. Chemical formulas:

• Calcium fluoride: \(Ca^{2+}\) and \(F^-\). To balance charges (\(+ 2\) and \(-1\)), formula is \(CaF_2\).
• Sodium oxide: \(Na^+\) and \(O^{2 - }\). To balance (\(+1\) and \(-2\)), formula is \(Na_2O\).
• Potassium bromide: \(K^+\) and \(Br^-\). Charges balance (\(+1\) and \(-1\)) → \(KBr\).
• Aluminum oxide: \(Al^{3+}\) and \(O^{2 - }\). LCM of 3 and 2 is 6. So \(2Al^{3+}\) (\(+6\)) and \(3O^{2 - }\) (\(-6\)) → \(Al_2O_3\).

Answer:

1.

• a) High
• b) Crystalline structures
• c) electricity
• d) Soluble
• e) Brittle

2.

• a. Sodium bromide
• b. Magnesium oxide
• c. Potassium sulfide
• d. Lithium oxide

3.

• a. \(Na^+\)
• b. \(F^-\)
• c. \(N^{3 - }\)
• d. \(Ca^{2+}\)
• e. \(Cl^-\)
• f. \(Al^{3+}\)
• g. \(O^{2 - }\)
• h. \(K^+\)

4.

• a. \(CaF_2\)
• b. \(Na_2O\)
• c. \(KBr\)
• d. \(Al_2O_3\)