Properties Of Ionic Compounds Trivia Quiz

1. Name the ionic compound with the empirical formula: K₂O

Calcium oxide

Potassium oxide

Sodium oxide

Barium oxide

The correct answer is Potassium oxide. Potassium oxide has the empirical formula K2O, which means it consists of two potassium ions (K+) and one oxygen ion (O2-). Calcium oxide (CaO), sodium oxide (Na2O), and barium oxide (BaO) do not match the given empirical formula.

Explanation

The correct answer is Potassium oxide. Potassium oxide has the empirical formula K2O, which means it consists of two potassium ions (K+) and one oxygen ion (O2-). Calcium oxide (CaO), sodium oxide (Na2O), and barium oxide (BaO) do not match the given empirical formula.

2. Select the formula for the following ionic compound, Aluminium Sulphide Hint: Cross mutliply (Al³⁺), (S^2-)

AlS

Al2S

AlS3

Al2S3

The formula for an ionic compound is determined by the charges of the ions involved. In this case, Aluminium has a charge of 3+ (Al3+) and Sulphide has a charge of 2- (S2-). In order to balance the charges, the subscripts of the elements in the formula must be such that the total positive charge equals the total negative charge. Since Aluminium has a charge of 3+ and Sulphide has a charge of 2-, it would take two Sulphide ions to balance out the charge of one Aluminium ion. Therefore, the correct formula for Aluminium Sulphide is Al2S3.

Explanation

The formula for an ionic compound is determined by the charges of the ions involved. In this case, Aluminium has a charge of 3+ (Al3+) and Sulphide has a charge of 2- (S2-). In order to balance the charges, the subscripts of the elements in the formula must be such that the total positive charge equals the total negative charge. Since Aluminium has a charge of 3+ and Sulphide has a charge of 2-, it would take two Sulphide ions to balance out the charge of one Aluminium ion. Therefore, the correct formula for Aluminium Sulphide is Al2S3.

3. These all are the characteristics of ionic compounds except

Soft

Conduct electricity when dissolved in water

High melting and boiling points

Crystal lattice structure

Ionic compounds are typically characterized by their high melting and boiling points, crystal lattice structure, and ability to conduct electricity when dissolved in water. However, they are not known for being soft. Ionic compounds are usually hard and brittle due to the strong electrostatic forces between the positive and negative ions in their lattice structure. Therefore, the correct answer is "soft".

Explanation

Ionic compounds are typically characterized by their high melting and boiling points, crystal lattice structure, and ability to conduct electricity when dissolved in water. However, they are not known for being soft. Ionic compounds are usually hard and brittle due to the strong electrostatic forces between the positive and negative ions in their lattice structure. Therefore, the correct answer is "soft".

4. Why do ionic compounds have such high melting and boiling points?

Ionic compounds have high melting and boiling points because of the strong electrostatic forces of attraction between the positive and negative ions holding the lattice together. These forces are very strong, requiring a lot of energy to break them apart. This is why ionic compounds have high melting and boiling points.

Explanation

Ionic compounds have high melting and boiling points because of the strong electrostatic forces of attraction between the positive and negative ions holding the lattice together. These forces are very strong, requiring a lot of energy to break them apart. This is why ionic compounds have high melting and boiling points.

5. When ions bond, they form a repeating three- dimensional pattern called ______.

A chemical compound

An ionic chalice

A crystal lattice

An ionic bond

When ions bond, they form a repeating three-dimensional pattern called a crystal lattice. This lattice structure is formed due to the strong electrostatic forces of attraction between the positively and negatively charged ions. The ions arrange themselves in a regular pattern, creating a solid crystal with a repeating unit cell. This arrangement allows for the stability and strength of the ionic bond between the ions.

Explanation

When ions bond, they form a repeating three-dimensional pattern called a crystal lattice. This lattice structure is formed due to the strong electrostatic forces of attraction between the positively and negatively charged ions. The ions arrange themselves in a regular pattern, creating a solid crystal with a repeating unit cell. This arrangement allows for the stability and strength of the ionic bond between the ions.

6. Determine the formula of the ionic compound formed when the following react. Magnesium and oxygen atoms

MgO2

CaO2

MgO

CaO

When magnesium reacts with oxygen, it forms an ionic compound called magnesium oxide (MgO). Magnesium loses two electrons to become Mg2+ ion, while oxygen gains two electrons to become O2- ion. The resulting compound has a 1:1 ratio of magnesium ions to oxide ions, giving the formula MgO.

Explanation

When magnesium reacts with oxygen, it forms an ionic compound called magnesium oxide (MgO). Magnesium loses two electrons to become Mg2+ ion, while oxygen gains two electrons to become O2- ion. The resulting compound has a 1:1 ratio of magnesium ions to oxide ions, giving the formula MgO.

7. When the ions in each pair combine to form ionic compounds, what will be the ratio of metal ion to non-metal ion? Mg²⁺ and Cl^-

2 Mg 2+ : 1 Cl-

1 Mg 2+ : 2 Cl-

2 Mg 2+ : 3 Cl-

1 Mg 2+ : 1 Cl-

The ratio of metal ion to non-metal ion in the ionic compound formed by Mg2+ and Cl- is 1:2. This means that for every 1 Mg2+ ion, there are 2 Cl- ions present in the compound.

Explanation

The ratio of metal ion to non-metal ion in the ionic compound formed by Mg2+ and Cl- is 1:2. This means that for every 1 Mg2+ ion, there are 2 Cl- ions present in the compound.

8. Indicate whether the following atoms will form cations and explain why.

Flourine. Reason- metal forms cation as it tends to lose electrons.

Calcium. Reason - non-metal forms cation as it tends to gain electrons

Flourine. Reason - non-metal forms cation as it tends to lose electrons.

Calcium. Reason - metal forms cation as it tends to lose electrons.

The correct answer is Calcium. Calcium is a metal and metals tend to lose electrons to form cations. When calcium loses two electrons, it forms a calcium ion with a +2 charge. This is because metals have fewer valence electrons and a lower electronegativity, making it easier for them to lose electrons and form positive ions.

Explanation

The correct answer is Calcium. Calcium is a metal and metals tend to lose electrons to form cations. When calcium loses two electrons, it forms a calcium ion with a +2 charge. This is because metals have fewer valence electrons and a lower electronegativity, making it easier for them to lose electrons and form positive ions.

9. In what form ionic compounds conduct electricity?

As a solid

As a liquid

When dissolved in water

When warmed slightly

Ionic compounds conduct electricity when dissolved in water because in their solid form, the ions are held tightly in a lattice structure and are not free to move. However, when the ionic compound is dissolved in water, the water molecules surround the ions, separating them from each other and allowing them to move freely. The ions then become mobile and can carry an electric charge, enabling the solution to conduct electricity.

Explanation

Ionic compounds conduct electricity when dissolved in water because in their solid form, the ions are held tightly in a lattice structure and are not free to move. However, when the ionic compound is dissolved in water, the water molecules surround the ions, separating them from each other and allowing them to move freely. The ions then become mobile and can carry an electric charge, enabling the solution to conduct electricity.

10. Why are ionic compounds brittle (shattered) when it is hit with a hammer?

When ionic compounds are hit with a hammer, the like-charged ions line up together and they repel due to electrostatic repulsion. This repulsion causes the crystal lattice structure of the ionic compound to break apart, resulting in the compound shattering.

Explanation

When ionic compounds are hit with a hammer, the like-charged ions line up together and they repel due to electrostatic repulsion. This repulsion causes the crystal lattice structure of the ionic compound to break apart, resulting in the compound shattering.