Experimental Design Scenario 1:
Investigation Question: Do tomatoes grow fastest under fluorescent, incandescent, or natural light?
Experimental Method: Get 3 of the same tomato plants planted in the same soil in the same temperature room. Water them at the same time one time per day with 100 mL of water. Place one plant under fluorescent light, one under incandescent light, and the last one under natural lights. Measure and record the plants growth with a ruler at the end of each day.
The independent variable is:
The dependent variable is:
Some control variables are:
Experimental Design Scenario 2:
Investigation Question: What concentration (amount) of salt water boils the fastest?
Experimental Method: Get 3 same-sized beakers and fill each beaker with 100 mL of the same source of water using a graduated cylinder. Heat the hot plate to 250℃. Measure 1.0 g of salt using the balance and add it to one of the water-filled beakers. In another beaker, add 5g of salt. In the third beaker, add 10g of salt. Measure how long it takes for the water to boil for each beaker using the hot plate.
The independent variable is:
The dependent variable is:
Some control variables are:
Which of the following is an example of physical change?
Which of the following is an example of physical change?
Which of the following is an example of chemical change?
What characteristic best describes what happens during a physical change?
Which is NOT usually a clue that could indicate a chemical change has occured?
What evidence BEST supports the claim: “Students should be involved in school activities.”