- 77 Views
- Uploaded on
- Presentation posted in: General

Solution Concentrations

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Solution Concentrations

Mass of solute

Mass of solution

×100

Solution = solute + solvent

An aquarium must contain 13.6 g NaCl per 100.0 g of water. What is the percent by mass (m/m) of NaCl in the solution?

Solute:13.6g (smaller #)

Solvent: 100.0g (larger #)

Solution: 113.6g

13.6

113.6

×100 = 11.97% ≈ 12.0%

+

You have a 650.0g KCL solution. If the percent by mass is 1.25% (m/m), how many grams of solute is in the solution? How many grams of solvent are in the solution?

Solution: 650.0g

Solute: 8.13g

Solvent = 641.87g ≈ 642g

solute

650.0

×100 = 1.25%

−

Solute = 8.13g

Volume of solute

Volume of solution

×100

Solution = solute + solvent

What is the percent by volume of ethanol in a solution that contains 45mL of ethanol dissolved in 145mL of water?

Solute: 45mL (smaller #)

Solvent: 145mL (larger #)

Solution: 190mL

45

190

×100 = 23.68% ≈ 24%

+

Means dissolved in water; water is the solvent

If you have 200.0 mL of a 35.0% aqueous solution of ethanol, what volume of ethanol and water are in the solution?

Solution: 200.0mL

Solute: 70.0mL

Solvent = 130.0mL

≈ 130. or 1.3×102 mL

solute

200.0

×100 = 35.0%

−

Solute = 70.0mL

Solute

Solution

×106

1 ppm = 1mg/L

If 25 grams of a chemical is dissolved in 75 grams of water, what is the concentration of the chemical in parts per million (ppm)?

Solute: 25g (smaller #)

Solvent: 75g (larger #)

Solution: 100g

+

25

100

×106 = 250,000 or 2.5×105 g

Suppose 17 grams of sucrose is dissolved in 183 grams of water. What is the concentration of sucrose in ppm?

Solute: 17g (smaller #)

Solvent: 183g (larger #)

Solution: 200g

+

17

200

×106 = 85,000 or 8.5×104g

150 mL of an aqueous sodium chloride solution contains 0.0045g NaCl. Calculate the concentration of NaCl in parts per million (ppm). Remember 1ppm = 1 mg/L

0.0045g1000mg1000mL

150mL 1g 1L

= 30 mg/L = 30 ppm

Convert 0.0035% NaCl by mass into parts per million of NaCl.

* Think of 0.0035% like your grade on a test; 0.0035% means 0.0035 out of 100

0.0035

100

×106 = 35ppm