2nd practice for Solutions, Acids and Bases

What term describes the highest concentration of a substance that can be dissolved in a solvent at a specific temperature?

• Solubility

• Concentration

• Mass

• A mixture

In the data shown in the graph below, the solubility of WHICH salt does not increase as temperature increases?

• NH₃
• KI
• NaCl
• KNO₃

Tags

NGSS.MS-PS1-4

Based on the solubility chart, which statement accurately describes the behavior of solubility with temperature changes?

• The solubility of NaCl remains constant as temperature increases.

• As temperature increases from 20°C to 80°C, the solubility of KNO₃ increases significantly.

• The solubility of NH₃ increases with an increase in temperature.

• Increasing the temperature of a NaNO₃ solution from 40°C to 80°C decreases its solubility.

Answer explanation

The correct choice states that as temperature increases from 20°C to 80°C, the solubility of KNO₃ increases significantly, which is supported by solubility charts showing that many salts, including KNO₃, become more soluble with higher temperatures.

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-4

Zoe is conducting an experiment to see how much sugar she can dissolve in different solutions at a constant temperature. In which solution would it be the easiest for her to dissolve additional sugar?

• saturated

• supersaturated

• suspended

• unsaturated

Which statement about electrolytes is incorrect?

• They can be found in solid form.

• They dissociate into ions in solution.

• They are capable of conducting electricity.

• All salts are considered electrolytes.

Answer explanation

The statement "They can be found in solid form" is incorrect because while many electrolytes are solids, they must dissolve in solution to dissociate into ions and conduct electricity, which is their defining characteristic.

Maya was making coffee and accidentally put too many scoops of coffee in the coffee maker. What type of coffee solution did she make and how could she fix the mistake without throwing the coffee away?

• You made a dilute coffee solution and can fix it by adding extra sugar to it

• You made a dilute coffee solution and can fix it by adding water to it

• You made a concentrated coffee solution and can fix it by adding extra sugar to it

• You made a concentrated coffee solution and can fix it by adding water to it

If you are making Gatorade by mixing the powder with water, which substance is the solute and why?

• Water; The Gatorade mix is a solid

• Gatorade mix powder; The Gatorade mix is a solid

• Gatorade liquid; The Gatorade mix is a solid

• Suger; The Gatorade mix is a solid

Answer explanation

The Gatorade mix powder is the solute because it is the solid substance being dissolved in water, which acts as the solvent. The resulting mixture is a solution of Gatorade.

Using the solubility curve, how would you classify a NaCl solution with 40 g of solute in 100 g of water at 80°C in terms of saturation?

• saturated

• unsaturated

• supersaturated

• Dilute

• Concentrated

Answer explanation

At 80°C, the solubility of NaCl is about 39 g per 100 g of water. Since the solution contains 40 g of NaCl, it exceeds the solubility limit, indicating it is unsaturated.

Which is NOT true of the solubility curve below?

• The higher the temperature, the greater the solubility.

• NaCl has the lowest solubility at 90 degrees Celcius.

• All of the substances above represent solid solutes.

• KNO₃ is least affected by a temperature increase.

Answer explanation

KNO₃ is actually highly affected by temperature changes, showing significant increases in solubility with rising temperatures. Therefore, the statement that KNO₃ is least affected by a temperature increase is NOT true.

Tags

NGSS.MS-PS1-4

NGSS.MS-PS3-4

Avery is conducting an experiment to dissolve additional salt in a saltwater solution. Which properties of the solution will allow the salt to dissolve the quickest?

• high temperature and high salt concentration

• high temperature and low salt concentration

• low temperature and low salt concentration

• low temperature and high salt concentration

Tags

NGSS.MS-PS3-4