Textbook Question
Which type (or types) of crystalline solid is characterized by each of the following? (d) network of covalent bonds.
Ch.12 - Solids and Modern Materials
Chapter 12, Problem 16
Indicate the type of solid (molecular, metallic, ionic, or covalent-network) for each compound: (a) InAs, (b) MgO, (c) HgS, (d) In, (e) HBr.
Verified step by step guidance1
Step 1: Understand the types of solids. Molecular solids consist of molecules held together by intermolecular forces. Metallic solids are composed of metal atoms with a 'sea of electrons'. Ionic solids are formed from cations and anions held together by electrostatic forces. Covalent-network solids have atoms connected by covalent bonds in a continuous network.
Step 2: Analyze compound (a) InAs. Indium arsenide (InAs) is a compound formed from indium (a metal) and arsenic (a metalloid). It forms a covalent-network solid due to the strong covalent bonds between the atoms in a continuous lattice structure.
Step 3: Analyze compound (b) MgO. Magnesium oxide (MgO) consists of magnesium ions (Mg²⁺) and oxide ions (O²⁻). The electrostatic attraction between these oppositely charged ions forms an ionic solid.
Step 4: Analyze compound (c) HgS. Mercury(II) sulfide (HgS) is composed of mercury and sulfur. It forms an ionic solid due to the ionic bonding between Hg²⁺ and S²⁻ ions.
Step 5: Analyze compound (d) In and (e) HBr. Indium (In) is a metal, so it forms a metallic solid. Hydrogen bromide (HBr) is a molecular compound, forming a molecular solid due to the weak intermolecular forces between HBr molecules.
Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Types of Solids
Solids can be classified into four main types: molecular, metallic, ionic, and covalent-network. Molecular solids consist of molecules held together by intermolecular forces, metallic solids are composed of metal atoms sharing electrons, ionic solids are formed from the electrostatic attraction between oppositely charged ions, and covalent-network solids consist of a continuous network of covalent bonds.
Recommended video:
Guided course
01:31
Crystalline Solids Structure
Ionic Compounds
Ionic compounds are formed when metals transfer electrons to nonmetals, resulting in the formation of positively and negatively charged ions. These ions are held together by strong electrostatic forces, creating a crystalline structure. Common examples include salts like sodium chloride (NaCl) and magnesium oxide (MgO), which exhibit high melting points and electrical conductivity when dissolved in water.
Recommended video:
Guided course
02:11Ionic Compounds Naming
Metallic and Covalent-Network Solids
Metallic solids consist of metal atoms that are bonded by a 'sea of electrons' that allows for conductivity and malleability. In contrast, covalent-network solids, such as diamond or silicon carbide, feature atoms connected by a network of covalent bonds, resulting in very high melting points and hardness. Understanding these distinctions is crucial for classifying the given compounds.
Recommended video:
Guided course
04:13Crystalline vs Amorphous Solids
Related Practice
Textbook Question
Indicate the type of solid (molecular, metallic, ionic, or covalent-network) for each compound: (a) CaSO4 (molecular, metallic, ionic, or covalent-network) for each compound: (b) Pd (molecular, metallic, ionic, or covalent-network) for each compound: (d) caffeine (C8H10N4O2) (molecular, metallic, ionic, or covalent-network) for each compound: (e) toluene (C7H8) (molecular, metallic, ionic, or covalent-network) for each compound: (f) P4.
Textbook Question
Indicate the type of solid (molecular, metallic, ionic, or covalent-network) for each compound: (c) Ta2O5 (melting point, 1872°C)
2
views
Textbook Question
You are given a gray substance that melts at 700 °C; the solid is a conductor of electricity and is insoluble in water. Which type of solid (molecular, metallic, covalent-network, or ionic) might this substance be?
Textbook Question
(a) Draw a picture that represents a crystalline solid at the atomic level.