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

Calculate the molarity and the molality of an $\mathrm{NH}_{3}$ solution made up of $30.0 \mathrm{g}$ of $\mathrm{NH}_{3}$ in $70.0 \mathrm{g}$ of water. The density of the solution is $0.982 \mathrm{g} / \mathrm{mL}$.

$$17.28 M$$, $$25.14 m$$

Chemistry 102

Chapter 12

Physical Properties of Solutions

Solutions

University of Central Florida

Drexel University

University of Kentucky

Lectures

03:58

In chemistry, a solution is a homogeneous mixture composed of two or more substances. The term "solution" is also used to refer to the resultant mixture. The solution is usually a fluid. The particles of a solute are dispersed or dissolved in the solvent. The resulting solution is also called the solvent. The solvent is the continuous phase.

05:06

In physics and thermodynamics, the natural tendency of a system to change its state is its tendency to increase the entropy of the system. It is a measure of the disorder in a system.

08:14

Calculate the molarity and…

01:35

A solution of $\mathrm{NH}…

06:56

Calculate the molality, mo…

07:32

08:26

Concentrated aqueous ammon…

04:01

02:33

An aqueous solution contai…

Okay, so we want them Larry ity and the morality off solution. Okay, so let's first start. But computing them polarity similarity will be number of most divided by the environment of the solution in leaders. So the first thing we need is the number of malls, right? The number of moles of ammonia. Okay, so we have 30 grams of ammonia. Okay? And to compute number of malls, basically, you need to use the molar mass. If you look that up, one mole of ammonia will have 17 grams. Okay, You compute that cancer, the grams final units will be more, which is what we want. You will have something like 1.76 mol. Okay, first step done. Now, we also need the volume of the solution. Okay? And we don't really have that. What we have is the density of the solution and the mass of the solvent, which is the water in the mass of the ammonia. So we can compute than mass off the solution, OK? And using that then city, then we can arrive at the volume of the solution. OK, remember, the density connects mass and volume, so let's do that. So now our destination is the volume off the solution. That's what we want. So first we need to complete the mass off the solution. So the mass of the solution will include that 30 grams of ammonia right here. And we have also to include, of course, the 70 grams of water. Okay. No, This will give us the mass of the fortune now using them density. We convert that to volumes. So basically, you divide this by density to get the units right. So I'm going to write here one Millie litter off the solution. You have 0.9 a two grams. Okay. And computing this sig figs depends on the east. You will get 200 to militar. Okay, so now you have all the data you need to compute the polarity. OK, so I'm going to represent the malarkey by this, um, capital M right here. And that will be the number of most that we computed on a talk. And we divide the by divine. But volume has to be in leaders, so I'm gonna convert that ready? Right? Should be a easy comforter. Just divide by 1000. Maintain the sig figs When you do unit converters. Okay. And there you doing this little calculation? We conclude that this, um oops. Worsen thing that I need to you. So this is the polarity off this wish in 17.2. Okay, Now, let's do the morality. And good thing is that we have already the number of malls, so we can use that. Okay, let's go down here. So for the Moleketi, we need the mass off the solvent. And we have that already. Right? We have the 70 grams of water so easy, we just go ahead. So I'm going to represent the morality with a little M. That would be the number of malls of the saw. You We computed that already. We concluded the 1.61 point 76 Mol. Okay. And the mass of the Sullivan will be the mass off water, which is 70 grams. Okay, 70 grams? No, of course you can convert, uh, two kilograms because it has to be in kilograms to be okay to be. Morality is defined in kilograms, so make sure that you do this conversion. I'm gonna just apply a conversion factor here, but you can do before. I'm just want to do it explicitly here. So I'm going to write. 1000 grams are equivalent to one kilogram. Okay? And that's it. So you compute that and you should get 25 20 25.2? No, for killing them. That's it.

View More Answers From This Book

Find Another Textbook

Numerade Educator

03:09

The men's world record for running a mile outdoors (as of 1999 ) is 3 m…

01:20

What is an amorphous solid? How does it differ from crystalline solid?

04:04

Based on your knowledge of the chemistry of the alkali metals, predict some …

01:27

Which of the following standard enthalpy of formation values is not zero at …

04:08

What is electron configuration? Describe the roles that the Pauli exclusion …

04:09

Define the following concentration terms and give their units: percent by ma…

03:34

Indicate which of the following sets of quantum numbers in an atom are unacc…

03:12

Define the following terms: crystalline solid, lattice point, unit cell, coo…

01:32

How would you prepare $60.0 \mathrm{mL}$ of $0.200 \mathrm{M} \mathrm{HNO}_{…

03:20

Sketch the outline of the periodic table and show group and period trends in…