Mid Unit 5 Assessment

Imagine Kingston, Madison, and Dakota are at a lemonade stand. Kingston stirs a spoonful of sugar into his lemonade. In this refreshing scenario, the sugar acts as the:

• Solute

• Solvent

• Solution

• Supernate

During a beach cleanup activity, Garrett, Hunter, and Lizbeth were tasked with separating substances found on the shore. They came across a mixture of different materials and needed to identify which one was insoluble in water to properly dispose of it. Can you help them choose the right answer?

• sand

• sugar

• salt

• baking soda

Ashton, Grace, and Chelsea are discussing the properties of solutions in their chemistry class. They are trying to identify which of the following statements about solutions is NOT correct. Can you help them?

• In covalent solutions water breaks up solute clumps into molecules which float in a distributed manner.

• In ionic solutions water breaks up solute into individual atoms/ions.

• Water being polar, only likes to dissolve other polar substances.

• The properties of gases and solids prevent them from becoming solutions.

Cordelle, Braydon, and Alex are conducting a kitchen experiment! They're trying to create the perfect syrup by dissolving sugar in water. Which of the following methods would NOT help the sugar dissolve more quickly?

• Stirring the mixture vigorously with a spoon.

• Grinding the sugar into finer particles before adding it to the water.

• Warming up the water before adding the sugar.

• Using less water for the same amount of sugar.

During a group project on environmental science, Emily, Cannon, and Chelsea are discussing the impact of various substances on aquatic ecosystems. They want to determine which substance does NOT become more soluble in water with increasing temperature, which could be detrimental to marine life. Can you help them resolve their debate?

• C₂H4O2 (sugar)

• NaCl (salt)

• K₂Cr₂O7 (potassium dichromate)

• O2 (oxygen gas)

During a fun science fair, Kingston, Dakota, and Neveah are demonstrating a cool experiment! They want to separate the colors in a drop of ink. Which scientific technique should they use, considering the homogenous nature of the ink?

• Chromatography, which uses a solvent to carry molecules of different size and speed.

• Combustion, which uses fire to burn the solute (not recommended for our young scientists!)

• Filtration, which uses filter paper to physically separate parts of a mixture such as sand and salt (but ink is too sneaky for that!)

• Spectrometer, which measures the concentration of molecules in a substance (great tool, but not for separation).

Imagine Mylan, Chelsea, and Lizbeth are chemists creating a saline solution. They heated their beaker until it could not dissolve any more salt. What do we call this concentrated solution at a given temperature?

• saturated

• unsaturated

• supersaturated

• diluted

Imagine Erik, Grace, and Neveah are chefs in a kitchen. They're experimenting with a new soup recipe and are curious to find out how much salt is needed to reach the perfect taste at 20°C. Can you help them with this fun cooking experiment?

• 30g

• 20g

• 90g

• 50g

Madison and Carson are conducting a chemistry experiment! They've just dissolved 20g of Sodium Chloride into 100g of water at a warm 50°C. What is the resulting state of the solution?

• Supersaturated

• Unsaturated

• Insoluble

• Immiscible

Imagine this: Alex and Chelsea are in their kitchen, trying to make rock candy. They've created a sugar solution that can't dissolve any more sugar at room temperature, then they gently heat the solution and add more sugar. After letting it cool, Corbyn drops a single sugar crystal into the mixture and suddenly, sugar crystals start to form on a string suspended in the solution. Can you guess what this type of solution is called?

• Supersaturated

• Unsaturated

• Insoluble

• Immiscible