Name:________________________________________Date:________________________

Unit 1: Scientific InquiryMrs. Bonewald

Aim #2: __________________________________________________________________________________________

1. How do scientists develop ideas for study or experiments?

Making observations and asking questions

2. Observations vs. Inferences

a. Observations- notice your surroundings using your five senses; facts

b. Inferences- assumptions based on your observations

observation

observation

inference

inference

inference

inference

inference

observation

inference

inference

Name:____________________________________Date:___________________________________________

Identifying and Making Observations and Inferences

Part 1 Directions: Fill in the missing word

(quantitative qualitative observationsinference)

One of the most important skills in science is the use of our five senses, or making observations. Most of the time we think of observing as something we do with our eyes; when we see something, we observe it. However, all five of our senses can be used to make observations: sight, hearing, taste, touch, and smell. A good scientist is observant and notices things in the world. He or she notices whats going on in the world and becomes curious about whats happening.

We can make two kinds of observations: either Qualitative or Quantitative. Qualitative data is information that is hard to measure, count, or describe in numbers. It describes the qualities or characteristics of something. Examples are colors, tastes, and smells. Quantitative data is information that can be expressed using numbers: something that can be counted or measured. Tools are often used to collect quantitative data. Examples include quantity, temperature, mass, and length. After we make observations, our brain makes logical conclusions about our observations called inference.

Part 2 Directions: Read the following sentences carefully. Determine if the sentence is an observation (O), an inference (I), or a prediction (P).

__________1. The mineral on the table is transparent and smooth. (O)

__________2. If I touch the hot pot handle I will burn my hand. (P)

__________3. The stream is not polluted.(I)

__________4. It must have rained before because there are many puddles. (I)

__________5. The stream velocity (speed) is 20 mph.(O)

Part 3 Directions: Read the following sentences carefully. For each sentence, underline the observation and circle the inference.

6. The people down the street must be having a barbeque because the air smells of smoke and burnt chicken.

7. There is a baseball in my driveway and my car windshield is broken. Someone playing ball must have shattered my windshield.

8. The rock has scratches and is very polished. This rock was once carved by a glacier.

Part 4 Directions: Look at the diagram below. Read the statement and determine if it is an observation or and inference. Write your answer on the line to the left.

__________9. The plant has roots.

__________10. The plant uses water.

__________11. The plant has flowers.

__________12. The plant has stems

__________13. The plant grew from a seed.

Part 5 Directions: Take a walk around your backyard or neighborhood. Make 3 observations and 3 inferences based on those observations about nature surrounding you. Be prepared to share them in class. Use the chart below to help organize your ideas.

Part 6 Directions: Use a blank piece of paper to cover up the three frames of the picture below. Uncover one frame at a time. While looking at each frame, make 3 observations. Then write a full sentence inference based on the observations youve made so far. After making the Frame 3 inference, Write a story (1-2 paragraphs) describing the events that may have occurred in this entire picture (Try to be as specific as possible).

Frame 1Frame 2Frame 3

Name:________________________________________Date:________________________

Unit 1: Scientific InquiryMrs. Bonewald

Aim #3: __________________________________________________________________________________________

1. Asking Questions and Identifying problems:

How to begin a scientific investigation:

2. HYPOTHESIS: an educated guess or

prediction of what will happen in an

experiment

- "If (Independent variable),

then (dependent variable)."

- "If (I change this variable),

then (this variable will respond).

Real World Example:

a. Which skills did Henri Becquerel display

that are essential to scientific inquiry?

b. What was his initial observation?

c. What did Becquerel do after he made is

observation?

Asking a Question and Creating a Hypothesis

A student is interested in designing several experiments to test the factors that affect how quickly an Alka-Seltzer tablet dissolves in water (solution rate). For each question, write an appropriate hypothesis that could be tested with an experiment.

Be sure each hypothesis is in the proper If, then , because format.

Example:

Question: What effect does stirring have on solution rate?

Hypothesis: If the water is stirred, then the tablet will dissolve faster because stirring increases solution rate.

Part 1

1. Question: What effect does the water temperature have on solution rate?

Hypothesis: If water temperature increases, than solution rate will increase.

2. Question: What effect does crushing the tablet have on solution rate?

Hypothesis: If the tablet is crushed, than solution rate will increase.

3. Question: What effect does adding soda to the water have on solution rate?

Hypothesis: If soda is added to the water, than the solution rate will increase.

Part 2: The next three questions are about factors affecting plant growth. For each question, write an appropriate hypothesis that could be tested with an experiment.

Be sure each hypothesis is in the proper If, then, because format.

4. Question: What effect does the amount of light have on plant growth?

Hypothesis: If plants are given more light, then they will grow taller.

5. Question: What effect does the amount of water have on plant growth?

Hypothesis: If plants receive more water then they will grow taller.

6. Question: What effect does using plant food (Miracle Grow) have on plant growth?

Hypothesis: If plants are given Miracle Grow then they will grow taller.

3. Experimental Design and Collecting Data

Experimental Design Reference

Scenario: A group of students is assigned a project in their ninth grade Earth Science class. They decide to determine the effect of sunlight on radish plants. They grow 12 radish plants in 4 clay pots with 25 mL of water daily and 100 g of potting soil in 24 hours darkness, 12 hours sunglight /12 hours darkness, and 24 hours sunlight. (They use Grow-Lights to simulate sunlight). After 5 days, they measure the height of all the plants in each pot.

1. Title: Communicates what your experiment is about.

The Effect of (the independent variable) on (the dependent variable.)

Example: The Effect of Amount of Sunlight on the Height of Radish Plants.

2. Hypothesis: Communicates what you think is going to happen in the experiment.

If (the independent variable) is (increased, decreased, changed), then (the dependent variable) will (increase, decrease, change).

Example: If the amount of sunlight is increased, then the height of the plants will increase.

3. Independent Variable: (IV) Also called the Manipulated Variable. The variable I purposely change or manipulate. Will be the CAUSE of the changes you measure.

Example: Amount of Sunlight

Experimental Groups: Will get varying levels of the independent variable

Example: 24 hours of darkness, 12 hours of sunlight/12 hours of darkness, and 24 hours of sunlight

Trials: The number of times each level is repeated. Could be the number of subjects tested, or

the number of times experiment is tested.

Example: 12 radish seeds in each pot = 12 trials for each level of sunlight

4. Dependent Variable: The variable that responds or the Data collected. Also called the Responding Variable. The variable you will measure after the experiment is set up. Will be the EFFECT of the action you took.

Example: The Height of the Plants

5. Constants: All of the other variables that remain the same for all the trials. Must be quantified. (Includes numbers.)

Example: 4 pots, 100g potting soil, 25 mL water daily

6. Control Group: The group that does not contain the varying levels of independent variable. The NO TREATMENT GROUP or NORMAL TREATMENT GROUP. Gives you way to compare the effect of the independent variable on the dependent variable to what is normal.

Example: the level in the above scenario that most acts like NORMAL for plants would be the 12 hours sun/12 hours dark. You are comparing the 24 hours darkness and 24 hours sunlight to the normal situation for plants.

Experimental Design Practice: Write a hypothesis for each of the statements and identify the variables, control group, and experimental group.

1. Cigarette smoking increases the risk of lung cancer.

Hypothesis: If _____________________________________________________________________________________, then ___