Molecular models of neutral molecules

Chemistry Lab

Lab 2 The Scientific Method

Student Name: Click here to enter text.

Access Code (located on the lid of your lab kit): Click here to enter text.

Pre-Lab Questions:

1. Which of the following are testable using scientific experimentation.

a. Are there more seeds in a medium sized Red Delicious Apple or a medium size Green Granny Smith Apple? Not testable

b. Why do people smoke cigarettes? Not testable

c. What happens to your blood glucose level if you do not eat lunch?

d. Which planet is the most interesting one to study?

e. Which objects are attracted by a magnet: a metal paperclip, copper penny, or aluminum foil? Testable

2. For each of the following questions, write a reasonable hypothesis using the “If__________ (independent variable), then_______________ (dependent variable)” format.

a. Does water affect the growth of a plant?

If then their growth rate will be affected and vice versa.

b. Does temperature affect the amount of sugar that dissolves into tea?

If then .

c. Does the volume of a container affect how quickly water will evaporate from it? If then .

Experiment 1: Testable Observations

Determine which of the following observations are testable. For those that are testable, answer the following:

Determine if the observation is qualitative or quantitative. Write a hypothesis and null hypothesis. What would be your experimental approach? What are the dependent and independent variables? What are your controls - both positive and negative?

Observations

1. A plant grows three inches faster per day when placed on a window sill than it does when placed on a coffee table in the middle of the living room.

Testable?- Hypothesis- Null Hypothesis- Experimental Approach- Dependent Variable- Independent Variable- Control(s)-

2. The teller at the bank with brown hair and brown eyes is taller than the other tellers.

Testable?- Hypothesis- Null Hypothesis- Hair and eyes color does not statistically determine the height of an individual Experimental Approach- Dependent Variable- Independent Variable- Control(s)-

3. When Sally eats healthy foods and exercises regularly, her blood pressure is 10 points lower than when she does not exercise and eats fatty foods.

Testable?- Hypothesis- Null Hypothesis- Experimental Approach- Dependent Variable- Independent Variable- Control(s)-

4. The Italian restaurant across the street closes at 9 pm, but the one two blocks away closes at 10 pm.

Testable?- Hypothesis- Null Hypothesis- Experimental Approach- Dependent Variable- Independent Variable- Control(s)-

5. For the past two days, the clouds have come out at 3 pm, and it has started raining at 3:15 pm.

Testable?- Hypothesis- Null Hypothesis- Experimental Approach- Dependent Variable- Independent Variable- Control(s)-

6. George did not sleep at all the night following the start of daylight savings.

Testable?- Hypothesis- Null Hypothesis- Experimental Approach- Dependent Variable- Independent Variable- Control(s)-

Experiment 2: Using the Scientific Method

Table 3: Number of Drops of Water that Fit on a Penny

Trial

Predicted # of Drops

Actual # of Drops

% Error

1

2

3

4

5

14

Average

N/A

Post-Lab Questions

1. Why did you perform more than one trial?

2. What are the benefits of repeated trials?

Insert a picture of your bar graph with your name clearly visible.

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Number of Trials

Bar graph of Actual drops vs Number of trials