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Vocabulary
Mixtures and Solutions
Concentration
Let's Experiment
Final Jeopardy
100
Define “mixture”
A mixture is a substance containing two or more materials
100
When you separate mixtures, you separate them by differences in their ____________.
properties
100
Which solution is the most dilute? Solution A: 12 grams of solid, 40 mL of water Solution B: 14 grams of solid, 40 mL of water Solution C: 16 grams of solid, 40 mL of water
Solution A is the most dilute. Since all three solutions have the same amount of solvent, the solution with the least amount of solute is the most dilute.
100
Max, Maria, and Mark each used 3 scoops of kosher salt to make solutions. Max used 900 mL of water to make his solution, Maria used 300 mL of water, and Mark used 700 mL of water. Rank their solutions in order from most concentrated to least concentrated.
Maria (most concentrated) Mark Max (least concentrated) Since they all have the same amount of solute, the solution with the least amount of solvent is most concentrated, and the solution with the most amount of solvent is the most dilute (least concentrated).
100
Below is a description of three solutions: Solution 1: 300 mL of water, 9 spoons of solid Solution 2: 200 mL of water, 8 spoons of solid Solution 3: 100 mL of water, 7 spoons of solid Which solution is most concentrated and how do you know?
Solution 3 is the most concentrated. Concentration is the comparison of the amount of solid (solute) to the amount water (solvent). If you want to compare these solutions, think about how much solute is dissolved in each 100 mL of water. solution 3 = 7 spoons per 100 mL solution 2 = 4 spoons per 100 mL solution 1 = 3 spoons per 100 mL
200
Define “solution”
A special mixture in which one or more materials dissolves into another
200
Can a cup of salt and water be both a mixture and a solution? Explain.
Yes. Mixtures are two or more materials mixed together, and salt and water are two materials. Salt and water is a solution because the salt dissolves into the water. All solutions are mixtures.
200
Which solution is more concentrated? Explain. Solution A: 4 scoops of solid, 50 mL of water Solution B: 9 scoops of solid, 100 mL of water
Solution B is more concentrated. If you doubled both the solute and solvent in solution A, both solutions would have the same amount of solvent, but there would still be more solute in solution B.
200
Kim made a solution with 2 spoons of salt and 50 mL of water. What can she do to make the solution more concentrated?
Add more salt to make it more concentrated.
300
Define “concentration”
The amount of solute dissolved in a measure of solvent
300
How would you separate a solution of citric acid and water? Describe what would happen to both materials.
Citric acid and water can be separated by evaporation. Water will go into the air (evaporate), and the citric acid will be left in the container (crystalize).
300
John made two solutions, described below: Solution A: 4 spoons of salt, 100 mL of water. Solution B: 8 spoons of a salt, 200 mL of water. Compare the concentrations of the two solutions.
The solutions have the same concentration. If you doubled both the salt and water in solution A they would have the same concentration.
300
Zoe made a solution with 8 spoons of salt and 100 mL of water. What can she do to make the solution more dilute?
Add more water to make it more dilute.
400
Name two ways you can dilute a solution
1) add less solute 2) add more solvent
400
How much does a mixture of 3 spoons of sand and 50 mL of water weigh if each spoon of sand weighs 4 grams? Show your work.
62 grams 50 mL of water = 50 g 3 spoons of sand = 12 g (3 x 4 g) 50 g + 12 g = 62 g
400
Describe how the concentration of a sugar and water solution changes as each spoon of sugar is added.
The concentration increases with each added spoonful of sugar.
400
Look at the data below. If you tried to layer each of these materials in a cup, show the order that the liquids would stack up: Water: Mass = 30 g, Volume 30 mL Alchohol: Mass = 20 g, Volume = 30 mL Oil: Mass = 25 g, Volume = 30 mL
All three liquids have the same volume, so the most dense liquid (highest concentration) would sink to the bottom and the least dense liquid (most dilute) would float on top. Bottom = water, Middle = Oil, Top = Alchohol
500
Define "property"
A property is a way of describing a material, such as size, color, shape, texture, etc.
500
How much does a solution of 2 spoons of salt and 100 mL of water weigh if each spoon of salt weighs 3 grams? Show your work.
106 grams 100 mL of water = 100 g 2 spoons of salt = 6 g (2 x 3 g) 100 g + 6 g = 106 g
500
Anna made two solutions using the same solid and water. Solution A: 6 spoons of solid, 50 mL of water Solution B: 5 spoons of solid, 40 mL of water Compare the concentrations of the two solutions.
Solution B is more concentrated than solution A. Solution B has 25 spoons of solid per 200 mL of water, while solution A has 24 spoons of solid per 200 mL of water.
500
Dan was making two solutions of sugar and water. He lost track of how much sugar he added to each, and the sugar is completely dissolved in each solution. How can he figure out which solution is more concentrated?
Fill two cups with equal amounts of each solution. Put both cups on either end of a pan balance. The heavier cup is the more concentrated solution.