The Scientific Method - Experimental Variables.

A scientist performs an experiment to see if acids have an effect on the health of a particular type of plant. Three sets of plants were treated with acidic solutions of known pH while the control set was treated with a solution of neutral pH 7. Which is the best conclusion for this experiment?

The graph below shows atmospheric carbon dioxide levels since the year 1880. Which of the following conclusions can be drawn from this graph? Options: Atmospheric carbon dioxide levels are responsible for global temperature change., Atmospheric carbon dioxide levels have been rising at about the same rate for the past century., Atmospheric carbon dioxide levels have remained the same over the past century., Atmospheric carbon dioxide levels have been rising at an increasingly higher rate as the past century has progressed.

In an appropriately designed experiment, a scientist is able to test the effect of

Which statement best expresses a basic scientific assumption? Options: Interpretation of experimental results has provided explanations for all natural phenomena., If a conclusion is valid, similar investigations by other scientists should result in the same conclusion., For any conclusion to be valid, the design of the experiment requires that only two groups be compared., After a scientist formulates a conclusion based on an experiment, no further investigation is necessary.

In an experiment to determine whether drinking caffeinated soda increases pulse rate, what is the dependent variable?

A series of steps used by scientists to solve a problem or answer a question.

There are two types of data. Which type of data involves numbers that are obtained by counting or measuring?

What type of variable is the fertilizer when experimenting with the growth of a plant using three plants, two different fertilizers, equal light, and equal water?

Research Question: Does the type of gasoline put in a car effect how fast the car can drive. What is the independent variable?

What step does every scientific experiment begin with? Options: hypothesis, question/problem, procedures, conclusion