Science Skills & Safety – Pre-Credit

If you are unsure about part of a lab procedure after reading the instructions, you should:

• Continue anyway and see what happens.

• Ask the teacher to clarify before proceeding.

• Skip the step and move on to the next one.

• Do a different assignment instead.

While doing a lab, someone knocks over a beaker and it breaks. What is the safest first step?

• Pick up the glass with your hands and throw it away.

• Tell the teacher, block off the area, and have them dispose of the glass properly.

• Sweep it up immediately without telling anyone.

• Have your partner clean it up.

A hypothesis is best described as:

• A proven fact.

• An educated guess that can be tested.

• A final conclusion from an experiment.

• A question that cannot be tested.

Which of these is a testable hypothesis?

• If salt is added to water, then the water will boil at a higher temperature.

• If a person feels happy, then they will have a better day.

During an experiment, the factor you measure or observe is called the:

• Independent variable

• Constant

• Dependent variable

• Hypothesis

At the end of a lab, you should:

• Return equipment but skip washing it.

• Wash your hands only if you used chemicals.

• Clean all materials, put them away, and wash your hands.

• Leave everything for the next class to clean.

Marco wanted to know which paper towel brand absorbs the most water. He placed each towel in a cup of water, let it soak, and then measured the water absorbed. He repeated the process for three brands.

• Brand of paper towel

• Amount of water absorbed

• Cup used

• Marco

In Marco’s paper towel experiment, what is the dependent variable?

• Brand of paper towel

• Amount of water absorbed

• Cup used

• Marco

In an experiment, the group that does not receive the independent variable and is used for

• Control group

• Experimental group

• Variable group

• Test group

A student thinks that tomato plants grow taller if given fertilizer. She plants two groups of tomato plants: one with fertilizer and one without. Which data would best test her hypothesis?

• Number of tomatoes produced

• Height of the plants in both groups

• Color of the leaves

• Type of soil used