Consider the lattice energies of the following Group 2A compounds: BeH 2 , 3205 kJ/mol; MgH 2 , 2791 kJ/mol; CaH 2 , 2410 kJ/mol; SrH 2 , 2250 kJ/mol; BaH 2 , 2121 kJ/mol. (a) What is the oxidation number of H in these compounds?

Hi everyone for this problem, we're told to consider the lattice energy of the following Group one A. Compounds. We need to identify the ionic charges in the listed compounds. So let's refer to our periodic table here. So our compounds all have GROUP one A elements. Okay. And when we refer to our periodic table, anything that is in Group one A. has a plus one ionic charge. But we also have sulfur. And all of the compounds. Okay. And when we refer to the periodic table, sulfur has a minus two ionic charge. And so That is it for this problem because it asks us to identify the ionic charges. So our group one a Are going to have a plus one ionic charge and our sulfur is going to have a -2 ionic charge. That's the end of this problem. I hope this was helpful.

Ch.8 - Basic Concepts of Chemical Bonding

All textbooks

Brown 14th Edition

Ch.8 - Basic Concepts of Chemical Bonding

Problem 79a

Chapter 8, Problem 79a

Consider the lattice energies of the following Group 2A compounds: BeH₂, 3205 kJ/mol; MgH₂, 2791 kJ/mol; CaH₂, 2410 kJ/mol; SrH₂, 2250 kJ/mol; BaH₂, 2121 kJ/mol. (a) What is the oxidation number of H in these compounds?

Verified step by step guidance

insert step 1: Understand that the oxidation number is a concept used to keep track of electrons in chemical reactions, particularly redox reactions.

insert step 2: Recognize that hydrogen typically has an oxidation number of +1 when bonded to nonmetals and -1 when bonded to metals.

insert step 3: Identify that in Group 2A metal hydrides (e.g., BeH2, MgH2), hydrogen is bonded to metals.

insert step 4: Conclude that since hydrogen is bonded to metals in these compounds, it will have an oxidation number of -1.

insert step 5: Verify that the sum of oxidation numbers in a neutral compound is zero, which supports hydrogen having an oxidation number of -1 in these metal hydrides.

Verified Solution

This video solution was recommended by our tutors as helpful for the problem above

Video duration:

Was this helpful?

Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Oxidation Number

The oxidation number, or oxidation state, is a theoretical charge assigned to an atom in a compound based on the assumption that electrons are completely transferred. In compounds, hydrogen typically has an oxidation number of +1 when bonded to nonmetals and -1 when bonded to metals. Understanding this concept is crucial for determining the oxidation states of elements in various compounds.

Group 2A Elements

Group 2A elements, also known as alkaline earth metals, include beryllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr), and barium (Ba). These elements typically have an oxidation state of +2 in their compounds due to the loss of their two outermost electrons. Recognizing the behavior of these metals helps in predicting the oxidation states of hydrogen in their hydrides.

Hydrides

Hydrides are compounds formed between hydrogen and other elements, where hydrogen can exhibit different oxidation states. In the case of alkaline earth metal hydrides, hydrogen is usually in the -1 oxidation state when bonded to metals. This understanding is essential for analyzing the oxidation states in the given Group 2A hydrides.

Recommended video:

Guided course

02:00

Ionic Hydrides

Related Practice

Textbook Question

Draw the Lewis structure for NO+ . Is the nitrogen– oxygen bond in NO+ longer, shorter, or the same length as the nitrogen–oxygen bond in NO? Explain. Draw the Lewis structure for NO+ .

1187

views

Open Question

A new compound has a C—O bond length of 120 pm. Is this bond likely to be a single, double, or triple C—O bond?

Open Question

A new compound is made that has a C—N bond length of 118 pm. Is this bond likely to be a single, double, or triple C—N bond?

Textbook Question

Consider the lattice energies of the following Group 2A compounds: BeH₂, 3205 kJ/mol; MgH₂, 2791 kJ/mol; CaH₂, 2410 kJ/mol; SrH₂, 2250 kJ/mol; BaH₂, 2121 kJ/mol. (c) Consider BeH₂. Does it require 3205 kJ of energy to break one mole of the solid into its ions, or does breaking up one mole of solid into its ions release 3205 kJ of energy?

Textbook Question

Consider the lattice energies of the following Group 2A compounds: BeH₂, 3205 kJ/mol; MgH₂, 2791 kJ/mol; CaH₂, 2410 kJ/mol; SrH₂, 2250 kJ/mol; BaH₂, 2121 kJ/mol. (d) The lattice energy of ZnH₂ is 2870 kJ/mol. Considering the trend in lattice enthalpies in the Group 2 compounds, predict which Group 2 element is most similar in ionic radius to the Zn²⁺ ion.

Open Question

A metal oxide has a lattice energy in the range of 3300 kJ/mol. Is the charge on the metal ion M likely to be 1+, 2+, or 3+? Explain.

Consider the lattice energies of the following Group 2A compounds: BeH2, 3205 kJ/mol; MgH2, 2791 kJ/mol; CaH2, 2410 kJ/mol; SrH2, 2250 kJ/mol; BaH2, 2121 kJ/mol. (a) What is the oxidation number of H in these compounds?

Recommended similar problem, with video answer:

Verified Solution

Key Concepts

Oxidation Number

Group 2A Elements

Hydrides

Consider the lattice energies of the following Group 2A compounds: BeH₂, 3205 kJ/mol; MgH₂, 2791 kJ/mol; CaH₂, 2410 kJ/mol; SrH₂, 2250 kJ/mol; BaH₂, 2121 kJ/mol. (a) What is the oxidation number of H in these compounds?