Question

EXPERIMENT: FORMS OF CHANGE

Here are your goals for this lesson:

Determine the change as physical or chemical
Write a scientific report including the specifications given in the experiment

A physical change is a change in the size and shape of a substance. Hardness, shape, mass, and density are physical properties which may be involved in a physical change. In a chemical change, however, new substances with different physical properties are produced.



In this investigation, you will be conducting a simple experiment. You will classify the result as a physical or chemical change. It is up to you to determine the type of change. Use the steps of the scientific method as you work.



EXPERIMENT

Supplies needed: sugar, beaker or dish, water, stirring rod or teaspoon

Instructions:

1. Place several teaspoons of sugar in a small beaker half full of water, and stir until the water is clear.

2. Pour some of the solution into a dish. Set the dish on a shelf or a windowsill. Observe the dish for a day or two. Record what you observe.



Compile a scientific report from your hypotheses, observations, data, inferences, and conclusions. Be sure to answer the questions below in your summary and include your personal findings.

What did you observe after the solution set in the dish for a day or two?

What kind of change (physical or chemical) occurred in this experiment?

How do you know the kind of change?

What happened to the sugar?

Name another mixture that could be separated in this way.

What did you find out from this experiment? Be thoughtful in your answer.

Answer 1

The sugar dissolved in water and then recrystallized after evaporation, indicating a physical change where the sugar's chemical identity remained the same.

Step-by-step explanation:

The experiment involved dissolving sugar in water and observing changes over a day or two. Observations likely include the sugar solution evaporating, leaving sugar crystals behind. This indicates a physical change, as the sugar's chemical composition remains unchanged; it has merely transitioned from dissolved in water to recrystallized form. Furthermore, drying sugar is a reversible process, further hinting at it being a physical change.

Another mixture that could be separated in the same way would be a saltwater solution; upon evaporation, the water would disappear as vapor, leaving salt behind. This experiment demonstrates the process of physical separation and evaporation, emphasizing that physical changes do not alter the substance's chemical identity.