Start typing, then use the up and down arrows to select an option from the list. # GOB Chemistry

Learn the toughest concepts covered in your GOB - General, Organic, and Biological Chemistry class with step-by-step video tutorials and practice problems.

Solutions

# Percent Concentrations

Percent Concentrations deal with the amount (in mass of volume) of solute found within a given solution.

## Mass and Volume Concentrations

1

#### concept

Percent Concentrations Concept 1 52s
Play a video:
Now recall that mass percent is the percentage of a given salute ingram's within a solution. Also in grams. And what we can understand is that additionally, we can use mass slash volume and volume percent formulas to express solution concentrations. Now here we're going to deal with what we call mass volume, abbreviated as M slash v percent concentration. We're going to say this represents a percentage of a given salute in grams dissolved in a given volume in milliliters of solution. So that means that our MV formula equals g of our salute, divided by ml of solution times 100%. So this will allow us to calculate the mass volume percentage for any given solution.
2

#### example

Percent Concentrations Example 1 55s
Play a video:
A solution was prepared by dissolving 13.5 g of potassium nitrate in sufficient water to produce 85 ml of solution. What is the mass volume percentage of this solution? Alright, so m so we're gonna stay here? M. V percentage equals the grams of our salute, divided by milliliters of our solution Times 100%. Here are salyut is the potassium nitrate, so that's 13.5 g of potassium nitrate, Divided by the mls of solution, which is 85 Times 100%. When we do that, we get 15.9%. As our final answer here, the answer has three sig figs, because both 13.5 and 85.0 also have three significant figures.
3

#### concept

Percent Concentrations Concept 2 26s
Play a video:
With volume volume percentages, we say, it represents a percentage of given salyut in middle leaders dissolved in a given volume of milliliters for solution. So that means that our volume volume percentage, so volume volume is abbreviated as v slash v percentage equals the mls of solute, divided by the mls of solution times 100%.
4

#### example

Percent Concentrations Example 2

The video is coming soon
here, we're told us 750 ml bottle of Listerine contains mls of ethanol. What is the volume volume percentage of this list during cleaning solution? All right, so, we're gonna say here, volume volume percentage equals the mls of salute, divided by the mls of solution Times 100%. So our salute is the is the ethanol. So it's 100 and 50 mls of ethanol. No, you don't need to know what the formula is here. I'm providing it, but you don't need to know it for this topic, divided by the Ml solution. Now, here's the thing. The solution is the 750 bottles of Listerine. So that's the entire amount of the bottle in terms of volume represents the volume of the solution So that the 750 mls of the solution Times 100%. So when we do that, we're gonna get here 20 as our percentage, our volume volume percentage. So here 150.0 has 46 figs. 1 50 has 26 figs. So I write it as 20 dot to signify that I have two significant figures with that volume volume percentage that I've obtained.
5
Problem

How many mL of ethanol are contained in a 750.0 mL bottle of wine that contains 11.0% (v/v) of ethanol?

6
Problem

Calculate the grams of solute needed to prepare the following:450 mL of a 2.0% m/v KOH solution.

7
Problem

What is the mass/volume percent concentration of the following solutions:0.075 mol sucrose (C12H22O11) in 270 mL of solution.

8
Problem

The pain reliever ibuprofen is sold as an oral suspension for children 2-11 years of age. How many milligrams would you obtain in a 2.7 tsp dose if it contains 100 mg per 5 mL? (1 tsp = 5 mL) 