Download the App!

Get 24/7 study help with the Numerade app for iOS and Android! Enter your email for an invite.

Get the answer to your homework problem.

Try Numerade free for 7 days

Like

Report

Consider the reaction $$\begin{aligned}\mathrm{N}_{2}(g)+3 \mathrm{H}_{2}(g) \longrightarrow 2 \mathrm{NH}_{3}(g) & \\\Delta H_{\mathrm{xn}}^{\circ}=&-92.6 \mathrm{kJ} / \mathrm{mol}\end{aligned}$$ If 2.0 moles of $\mathrm{N}_{2}$ react with 6.0 moles of $\mathrm{H}_{2}$ to form $\mathrm{NH}_{3},$ calculate the work done (in joules) against a pressure of 1.0 atm at $25^{\circ} \mathrm{C}$. What is $\Delta U$ for this reaction? Assume the reaction goes to completion.

$w=4.957 k J$$\Delta E=190 . k J$

Chemistry 101

Chapter 6

Thermochemistry

Drexel University

University of Kentucky

Lectures

05:27

In chemistry, a chemical reaction is a process that leads to the transformation of one set of chemical substances to another. Both reactants and products are involved in the chemical reactions.

06:42

In chemistry, energy is what is required to bring about a chemical reaction. The total energy of a system is the sum of the potential energy of its constituent particles and the kinetic energy of these particles. Chemical energy, also called bond energy, is the potential energy stored in the chemical bonds of a substance. Chemical energy is released when a bond is broken during chemical reactions.

03:22

Consider the following rea…

09:28

Consider the reaction$…

02:19

Consider the reaction $$\b…

03:32

04:02

`Consider the reaction…

this is sort of a big problem, and we're going to start by looking at our reaction. Nitrogen gas reacts with hydrogen gas to produce ammonia and by Delta H for this reaction equals negative 92.6 killer jewels per mole. Okay, that's given. And we are also given that we have 2.0 moles of end to and we have 6.0 bulls of age too. That's what I'm given here. Also, I'm given that I am at 1.0 atmospheres of pressure and 25 degrees seat. Okay, were asked to find, calculate work, find work in jewels. This is one of our unknowns. And second is what is the Delta U. So we have two things to dio. Okay, so what we're going to do on this one is we are our plan. Let me switch colors for a plan here for a plan we're going to use PD equals inner t. And on this one we're going to solve for V, our second order of business will be to use. Ah, work equals that negative p times dealt to be will be finding our work. Um, when we find our work we're also going to be. We've already got our Delta Ages, but we're going to figure out Delta H for the conditions given and then for our delta u will be doing our Let me see here will be doing our, um, work and killer jewels plus our delta h. So that's our plan. Let's start first we said we were going to use, um let's evaluate a problem. We have to 0.0 moles of nitrogen and we have 6.0 moles of hydrogen for a total of 8.0 moles of gas and that 8.0 moles of gas will yield a product 4.0 moles of product. So what we're seeing here is a loss of four moles. We have a loss of four moles of gas. Now we're going to use that into solving for V. P equals nrt is and our T overpay. So let's go ahead and solve this. We've got V equals 4.0 malls and our are will be since we're an atmosphere 0.0 8 to 1 l A t m overcame all our temperature was 25 c, which is to 98 k and our pressure very nicely is one. Do my math here. And my Delta V will be 98 leaders, 98 leaders. And that's 98 leaders. Um, decrease. That's a decrease. So that'll be a negative number because we went from eight, 24 Okay, Now our next order of business is to use. I'm gonna go there next page. We're going to use our work equals negative p times Delta v. So this we're gonna have negative 1.0 atmospheres times a negative 98 leaders. I'm gonna go back. Make sure it was 98. Yep. Negative. 98 leaders. Okay, that will equal 98 leaders. I need to convert that using our conversion factor of 101 101 0.3 Jules per leader. Atmosphere. That's leader atmospheres. Cross cross equals and this will get me, um, 99 100 jewels, which is 9.9 killer jal's. There's my work. Answer. That's the answer for work. Okay, that's simply enough. Now, we also have to find our Delta U. And that's going to be the sum of Delta H and W. So I've got my 9.9 killer jewels right here. That's my X. What's this going to be? Well, if we go back to go back to original problem here, we've got negative 92.6 Killer jolt per mole. And I've got two moles of this. So I've got negative 92.6 killer jewels, and that is for two malls. That's for two moles. But I have four moles because of the numbers that I was given. So I need to double that. So I've got negative one. 85.2. I just did that in my head. Negative. 1 85.2 What's wrong, page? The number that goes right here is going to be 95. Where is that number? 92.6 Negative. 92.6 killed joules per mole. Times two. So it'll be negative. 1 80 5.2. Okay, I'm gonna raise this and x X will equal negative 1 75.3 killer jewels. That's killer JAL's as well. So that's my delta W or dull to you. There's Delta U, and there's work

View More Answers From This Book

Find Another Textbook

Numerade Educator

01:58

Referring to Problem $9.137,$ describe the hybridization state of the $\math…

07:31

What is the original molarity of a solution of formic acid (HCOOH) whose pH …

01:00

Give equations to show that molecular hydrogen can act both as a reducing ag…

02:14

The sun is surrounded by a white circle of gaseous material called the coron…

05:34

Balance the following redox equations by the ionelectron method:(a) $\ma…

03:57

Define the following terms: enthalpy of solution, heat of hydration, lattice…

09:09

All molecules undergo vibrational motions. Quantum mechanical treatment show…

02:41

A $0.054 M \mathrm{HNO}_{2}$ solution is titrated with a KOH solution. What …

07:49

An impure sample of zinc (Zn) is treated with an excess of sulfuric acid $\l…

04:59

Calculate the work done in joules by the reaction $$2 \mathrm{Na}(s)+2 \math…