Chapter 5, Problem 89GQ

### Chemistry & Chemical Reactivity

10th Edition
John C. Kotz + 3 others
ISBN: 9781337399074

Chapter
Section

### Chemistry & Chemical Reactivity

10th Edition
John C. Kotz + 3 others
ISBN: 9781337399074
Textbook Problem

# Chloroform, CHCl3, is formed from methane and chlorine in the following reaction.CH4(g) + 3 Cl2(g) → 3 HCl(g) + CHCl3(g)Calculate ΔrH°, the enthalpy change for this reaction, using the enthalpies of formation of CO2(g), H2O(ℓ), CHCI3(g) (ΔfH° = –103.1 kJ/mol), and the enthalpy changes for the following reactions:CH4(g) + 2 O2(g) → 2 H2O(ℓ) + CO2(g)ΔrH° = –890.4 kJ/mol-rxn2 HCl(g) → H2(g) + Cl2(g)ΔrH° = +184.6 kJ/mol-rans

Interpretation Introduction

Interpretation:

The enthalpy change for the reaction of has to be calculated.

Concept Introduction:

The standard enthalpy change of combustion of a compound is the enthalpy change which occurs when one gram of the compound is burned completely in oxygen under standard conditions, and with everything in its standard state.

ΔrH0ΣnΔfH0(products)-ΣnΔfH0(reactants)

Explanation

Given,

CH4+â€‰2O2â†’â€‰2H2OÂ +Â CO2Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â  Î”fH0-890.4kJ

Reverse the 2nd equation and multiply by 3.

3/2Â H2Â +Â 3/2Cl2â€‰â†’â€‰3HClÂ Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â  Î”fH0-276.9kJ

Inorder to consume the CO2 formed in the 1st equation reverse the formation of CO2.

CO2â†’CÂ +Â O2Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â  Î”fH0-393.5kJ

In order to consume the H2O formed in the 1st equation reverse the formation of H2O

### Still sussing out bartleby?

Check out a sample textbook solution.

See a sample solution

#### The Solution to Your Study Problems

Bartleby provides explanations to thousands of textbook problems written by our experts, many with advanced degrees!

Get Started