Download the App!

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

The combustion of a 25.0 -g gaseous mixture of $\mathrm{H}_{2}$ and $\mathrm{CH}_{4}$ releases $2354 \mathrm{kJ}$ of heat. Calculate the amounts of the gases in grams.

Get the answer to your homework problem.

Try Numerade free for 7 days

Like

Report

mass of $\mathrm{H}_{2}=11.2 \mathrm{g}$mass of $\mathrm{CH}_{4}=13.8 \mathrm{g}$

Chemistry 101

Chapter 6

Thermochemistry

Carleton College

University of Central Florida

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.

02:07

When 2.50 g of methane bur…

00:58

01:22

02:56

How much heat is released …

03:05

The complete combustion of…

01:41

Burning $1.43 \mathrm{g}$ …

01:03

Methane burns with oxygen …

01:46

02:36

The equation for the combu…

04:15

The standard enthalpy of c…

05:22

What mass of natural gas (…

01:31

Okay, We're gonna be working on a combustion problem, and this one is rather challenging. So let's get started. Here's what we're given. We are given 25.0 grams of a gaseous mixture. This is a mixture of hydrogen gas and methane, and we know that the heat released The heat released is 2300 54 killer jewels, and we are asked to calculate find the mass of each gas. Okay, so let's get started. First, we're going to write two equations first for water or against hydrogen. And this one we don't even have to really do. A big calculation on this is to 85.8 killer jewels per mole. And we know that because both of these are zero, and that's negative to 85.8. Okay, for the next one, I better go to the next page for methane. We've got ch four plus o two, and this will yield CO two and aged. Well, looking up our values for these, I've got negative to 85.8 killer jewels per mole. All this isn't balanced. Let me go ahead and balance this. There we go. And there okay. And we've got negative 3 93.5 zero. And this one, I believe, was negative. 74.9. Remember that? Its products minus reacted. It's so products will be one times negative. 3 93.5 gila jewels per mole. Plus two times negative to 85.8 killing joules per mole. There's my products, and then I'm going to subtract. I'm gonna see if I could make this just a little bit better. Subtract negative. 74.9. And, of course, I can't fit that on there. So I'm gonna put this on the next line minus negative. 74.9 killer jewels per mole. Okay, easy enough to solve this one. And I got, I believe, eight in a negative negative eight. I think it was 90.3. No, it was 90.2890 Plane to killer jewels. Promote. Okay, that's step one. Now, let's think about what else we know. We know that, um, the mass of hydrogen plus the mass of methane equals 25.0 grams. So let's go ahead. And, um, we'll just, like, figure out one of these. I don't really care which one of these, we figure out. Lets do em. Oh, let's just pick C H four and that's gonna equal 25 0.0 grams minus M h two. So we're going to substitute this into the equation. I'm going to start on the next page. Okay, so we know the amount of heat released per mole of each substance. We just calculated that for H two, it was negative to 85 point eight killer jewels per mall. And for C H four, it was negative. 890.2 Killer jewels promote. We also know the Moeller may ask for each of our substances. This one is 2.2 That's shouldn't have a minus there. That's just molar mass. I'm grams grams per mole, and methane is 16.4 maybe 05 grams per mole. There we go. So that's everything that we're going to need to know right now. So we also know that we had 2000 354 killer jewels, total heat. So now we're going to do our H two calculation plus R c h four calculation, and I doubt I'll get these in the same line, but we'll figure it out. So the mass of hydrogen times the molar mass of hydrogen is one mall over 2.2 grams times negative. All right, we don't have to put the signs there to 85 point eight Kila jewels. Permal. So my moles and this will be grams and there's my killer. JAL's okay. And now I'm going to raise a little bit here. Now for my we're gonna add to this Think I'll change colors Plus now for the M C. H four. We figured out on our previous page that 25.0 grands minus the mass of age to And then we're going to have one mole over 16.5 grand's times 890.2 Kill a Jules per mall. Oh, very good. OK, do your math. Do our math door math and I When I'm done solving this, I'll have a mass of 11.2 grams for hydrogen. And then for the mass of mice method, it will just be 25.0. Minus 11.2 equals 13.8 grams of methane. Okay, not too bad

View More Answers From This Book

Find Another Textbook