Vocabulary
2 or more materials stirred together
Mixture
The recipe on a package of a powdered drink mix calls for 3 scoops of powder and 500 mL of water. If I want to double the recipe, how much water and powder do I need?
6 scoops of powder and 1,000 mL of water
Which liquid is the most useful in making solutions?
water
How would you test an unkown material to see if it dissolves in water?
Stir the material in water. If it "disappears," then it dissolves in water.
A spoon of baking soda is 5 g. A cup of vinegar is 50 g. These materials are mixed together in an open cup. The mixture bubbles when the materials are mixed.
If you did this same investigation with the cup sealed, what would you expect the mass to be after the bubbling stops?
The same- 55 g
When the liquid turns to gas and disperses into the air, leaving any dissolved solid material behind.
Evaporate
A spoon of baking soda is 5 g. A cup of vinegar is 50 g. These materials are mixed together in an open cup. The mixture bubbles when the materials are mixed.
What would you expect the materials in the cup to weigh after the bubbling stops?
The mass in the cup is less than 55 g
A student adds three spoons of solid to 100 mL of water. The solution is clear, with nothing on the bottom of the cup. One spoon of the solid has a mass of 5g.
What is the mass of the solution?
115 g
As one part of the solution evaporates, does the concentration increase or decrease?
increases
A student adds three spoons of solid to 100 mL of water. The solution is clear, with nothing on the bottom of the cup. One spoon of the solid has a mass of 5g.
After the water evaporates, what is the mass of the solid remaining in the cup?
15 g
When solid material is added to a solution until no more will dissolve.
Saturated
What is one way you could separate a dry mixture of diatomaceous earth (powder) and salt?
Add water and stir
Use filter paper to seperate powder from water
Evaporate water from the solution
(See the graph from teacher)
If the salt water solution in the cup on the balance contains 100 mL of water, about how much salt does it contain?
15 g
Your aunt is making a casserole for Thanksgiving dinner. She put the following ingredients into the dish:
25g of soup
100g of chicken
100g of chicken broth
50g of French-fried onions
75 g of cheese
How much will your aunt's casserole (mixture) going to weigh before she bakes it?
350 grams
(See the graph from the teacher)
According to the graph, which substance is the MOST SOLUBLE in water?
Citric Acid
The solid that dissolves in the liquid part of the solution
Solute
Ben and Tom had a mixture of salt and water, and diatomaceous earth. They wanted to separate the diatomaceous earth from their mixture.
What would be the BEST way to complete this separation?
Pour the mixture through a filter and rinse with water
(See the table from the teacher)
James and Ben observed two different Kool-Aid solutions and recorded their observations in the table shown. They decided that Solution A is more concentrated than Solution B.
What evidence do they have to support their conclusion?
C.) Solution A was darker and sweeter.
Students had two containers containing white powder. Select each method that could be used to determine whether the powders are the same substance.
Select ALL correct responses.
(See responses from teacher)
Solution A was darker and sweeter
When you evaporate a solution, what is evaporating and what is being left behind?
Water (solvent) evaporates, and the solid (solute) is left behind.
The liquid part of a solution
Solvent
(See the graph from the teacher)
Ms. T and Jim used salt and water to make mixtures 1,2, 3, as shown in the graph.
If they made mixture 2 with two spoons of salt, what do you think they would observe?
B.) Clear- nothing on bottom
Morgan and Kay mix two solid materials together, add water, and stir. The mixture starts to bubble. After a few minutes, the liquid is clear, and there is solid material floating on top of the liquid. They use a paper filter to separate the floating solids from the liquid. What could they do to determine if the liquid that went through the filter is a solution?
A. Add baking soda and see if the liquid fizzes
B. Add food coloring to see if there are solid particles
C. Put the liquid in an open container to see if any solid remains after the liquid evaporates.
D. Put the liquid in a container with a lid and see if any solids start to form at the bottom.
A.) Add baking soda and see if the liquid fizzes
Your friend tells you his solution is saturated. How can he tell?
When the solution can't dissolve any more solute, it will start to stay on the bottom.
(See teacher for prompt and models)
Which model best explains what the chemist saw after 2 days?
C.) Some of the water evaporated, but not the solid, so the concentration of the solution increased.