Ionic, covalent, metallic bonding, giant structures: แบบฝึกหัด

Which of the following best describes the bonding in a sample of copper (\(Cu\)) metal?

Which of the following substances is expected to be an electrical insulator in the solid state but becomes an electrical conductor when it is melted?

Metal \( X \) adopts a body-centered cubic (BCC) lattice, while metal \( Y \) adopts a cubic close-packed (CCP) lattice. Which of the following statements concerning these metals is/are correct?

(1) The coordination number of an atom in metal \( X \) is lower than that in metal \( Y \).
(2) Metal \( Y \) has a higher packing efficiency than metal \( X \).
(3) Both metals are held together by the electrostatic attraction between a 'sea' of delocalized electrons and positively charged metal ions.

Which of the following statements correctly compares the bonding and structures of potassium chloride (\(KCl\)) and silicon dioxide (\(SiO_2\))?

Which of the following statements concerning the bonding and structures of chemical substances is correct?

Identify the type of particles that occupy the lattice positions in a giant covalent structure, using diamond as an example.

Explain, in terms of structure and bonding, why ice has a lower density than liquid water at \(0^\circ C\).

Silicon dioxide (\( \text{SiO}_2 \)) and diamond are both examples of giant covalent structures. Explain why diamond has a higher melting point than silicon dioxide.

Nitrogen (\(N_2\)) is a diatomic molecule that makes up a large part of the Earth's atmosphere.
(a) Draw the electron diagram for a nitrogen molecule, showing valence electrons only.
(b) State the number of shared electrons in the covalent bond between the two nitrogen atoms.
(c) Explain why nitrogen has a very low boiling point (\(-196 ^\circ C\)) in terms of its structure and bonding.
(d) Explain why nitrogen gas is generally chemically inert (unreactive) at room temperature.

Pure copper and brass (an alloy of copper and zinc) are metallic substances that exhibit different physical properties.

(a) Describe the metallic bonding in pure copper with reference to the 'sea of delocalised electrons' model.

(b) Explain why brass is harder and less malleable than pure copper by referring to their atomic arrangements.

(c) Copper reacts with chlorine gas to form copper(II) chloride (\(CuCl_2\)). Identify the type of bonding in this compound and describe how the particles are held together in its giant structure.