10-minute Quiz : Chapter 8 Covalent bonding

The table below shows the electronic arrangements of four elements. Which of the following two elements combine to form a covalent compound?

• A. W and X

• B. W and Y

• C. X and Y

• D. X and Z

A phosphine molecule (PH₃) forms a phosphonium ion with a hydrogen ion. The electron diagram of a phosphonium ion is shown below. Which of the following statements concerning a phosphonium ion are correct?

(1) Its formula is PH₄⁺.

(2) A dative covalent bond is present in the ion.

(3) There are no lone pairs of electrons in the ion.

• A. (1) and (2) only
• B. (1) and (3) only
• C. (2) and (3) only
• D. (1), (2) and (3)

Which of the following types of bonding can be found in (NH₄)₃PO₄?

(1) Ionic bond

(2) Dative covalent bond

(3) Metallic bond

• A. (1) and (2) only
• B. (1) and (3) only
• C. (2) and (3) only
• D. (1), (2) and (3)

The following diagram represents a compound. Which of the following statements are correct?

(1) The above diagram is the structural formula of the compound.

(2) The compound consists of three elements.

(3) There are 12 bond pairs of electrons in the compound.

• A. (1) and (2) only
• B. (1) and (3) only
• C. (2) and (3) only
• D. (1), (2) and (3)

Which of the following compounds does NOT contain a double bond?

• A. CO₂
• B. C₂Cl₄
• C. C₂F₆
• D. C₂H₂Br₂

Which of the following diagrams represents the arrangement of particles in a covalent compound?

• A
• B
• C
• D

The electron diagram of a compound formed from elements X and Y is shown below (only the outermost shell electrons are shown). The compound could be

• A. methane.
• B. ammonia.
• C. sulphur dioxide.
• D. silicon tetrachloride.

Which of the following combinations about the names and formulae of covalent compounds is INCORRECT?

• A
• B
• C
• D

Which of the following statements concerning manganese(IV) oxide (MnO₂) are correct?

(Relative atomic masses: O = 16.0, Mn = 54.9)

(1) It is an ionic compound.

(2) Its relative molecular mass is 86.9.

(3) Its formula mass is 86.9.

• A. (1) and (2) only
• B. (1) and (3) only
• C. (2) and (3) only
• D. (1), (2) and (3)

Which of the following substances has the greatest formula mass?

(Relative atomic masses: Li = 6.9, O = 16.0, F = 19.0, Cl = 35.5, K = 39.1, Ca = 40.1, Br = 79.9)

• A. Calcium chloride
• B. Potassium fluoride
• C. Lithium bromide
• D. Calcium oxide