Question

jon is using a wet rag to wipe down the countertops in his kitchen. he notices that the rag seems to dissolve substances and clean better when he wets the rag with hot water. jon wonders what factors affect the rate at which water can dissolve a substance. he has the following supplies available: tap water, two heat - safe bowls, two spoons, sugar, a hot plate, a refrigerator, a stopwatch. using only these supplies, which two questions can jon investigate with an experiment? does tap water heated on a hot plate dissolve sugar faster than it dissolves salt? does sugar dissolve faster in tap water or distilled water? does tap water heated on a hot plate dissolve sugar faster than tap water chilled in a refrigerator does? does tap water dissolve sugar faster when it is stirred with a spoon?

Explanation:

Step1: Analyze available supplies

Jon has tap - water, two heat - safe bowls, two spoons, sugar, a hot plate, a refrigerator, and a stopwatch.

Step2: Evaluate each question

• For "Does tap water heated on a hot plate dissolve sugar faster than it dissolves salt?": He has no salt, so cannot test this.
• For "Does sugar dissolve faster in tap water or distilled water?": He has no distilled water, so cannot test this.
• For "Does tap water heated on a hot plate dissolve sugar faster than tap water chilled in a refrigerator does?": He can heat water on hot - plate, chill water in refrigerator, use sugar, bowls, and stopwatch to time the dissolving.
• For "Does tap water dissolve sugar faster when it is stirred with a spoon?": He can use tap water, sugar, spoon, bowls, and stopwatch to time the dissolving with and without stirring.

Answer:

Does tap water heated on a hot plate dissolve sugar faster than tap water chilled in a refrigerator does?
Does tap water dissolve sugar faster when it is stirred with a spoon?