DO NOW: In your binder, answer the following questions in complete sentences. What is a constant? Why are constants important to have when conducting an experiment? Learning Target : I can prepare for our exam on the scientific method and experimental design. 5 minutes

What is a constant? PAIR & SHARE 1 minute With your partner, share your definition of the word constant. Why are constants important to have when conducting an experiment?

What is a constant? PAIR & SHARE 1 minute With your partner, share your definition of the word constant. Why are constants important to have when conducting an experiment? The purpose of constants are to ensure that the experiment is testing only the independent variable’s effect on the dependent variable.

Experimental DeSign Beetles are eating Alyssa’s tulips in her backyard. She wants to test some household chemicals to see if they will kill the beetles. She uses mouthwash, windex, and laundry detergent in equal amounts. She will evaluate the beetle population after one week to determine which chemical killed the most beetles.

Experimental Design Beetles are eating Alyssa’s tulips in her backyard. She wants to test some household chemicals to see if they will kill the beetles. She uses mouthwash, windex, and laundry detergent in equal amounts. She will evaluate the beetle population after one week to determine which chemical killed the most beetles. IDENTIFY THE… 1. Independent Variable__________________________ 2. Dependent Variable___________________________ 3. Control Group______________________________ 4. Experimental Group___________________________ Experimental DeSign

Experimental Design Beetles are eating Alyssa’s tulips in her backyard. She wants to test some household chemicals to see if they will kill the beetles. She uses mouthwash, windex, and laundry detergent in equal amounts. She will evaluate the beetle population after one week to determine which chemical killed the most beetles. 1. Independent Variable = The household chemical used 2. Dependent Variable = The number of living beetles 3. Control Group = The tulips not sprayed with chemicals 4. Experimental Group = The tulips sprayed with chemicals Experimental DeSign

Experimental Design Charlie wanted to find out which dish washing liquid soap was best for removing stains from his dishes. Each soap was mixed with warm water. It was then used to scrub a food-stained dish for 1 minute. Then the amount of stain left on the dish was measured.

Experimental Design Charlie wanted to find out which dish washing liquid soap was best for removing stains from his dishes. Each soap was mixed with warm water. It was then used to scrub a food-stained dish for 1 minute. Then the amount of stain left on the dish was measured. IDENTIFY THE… 1. Independent Variable__________________________ 2. Dependent Variable___________________________ 3. Control Group______________________________ 4. Experimental Group___________________________ Experimental Design

Charlie wanted to find out which dish washing liquid soap was best for removing stains from his dishes. Each soap was mixed with warm water. It was then used to scrub a food-stained dish for 1 minute. Then the amount of stain left on the dish was measured. 1. Independent Variable = The brand of dish washing liquid 2. Dependent Variable = The amount of stain remaining 3. Control Group = Dishes washed with original/generic brand of dishwashing liquid 4. Experimental Group = Dishes washed with different brands of dishwashing liquid Experimental Design

Why do scientists conduct an experiment multiple times rather than rely on a single trial?

Experimental Design Why do scientists conduct an experiment multiple times rather than rely on a single trial? Scientists conduct an experiment multiple times rather than a single trial for two reasons. First, they want to avoid error. Second, they conduct multiple trials to end with accurate and reliable results. Experimental Design

A skin care company wants to show a reduction in blemishes with their new formula of face wash. Hypothesis:

Experimental Design A skin care company wants to show a reduction in blemishes with their new formula of face wash. Hypothesis: IDENTIFY THE… 1. Independent Variable__________________________ 2. Dependent Variable___________________________ 3. Control Group______________________________ 4. Experimental Group___________________________

The Scientific Method Let’s arrange the steps of the scientific method in order…

The Scientific Method

Let’s arrange the steps of the scientific method in order… The Scientific Method

Let’s arrange the steps of the scientific method in order… The Scientific Method

Let’s arrange the steps of the scientific method in order… The Scientific Method

Let’s arrange the steps of the scientific method in order… The Scientific Method

Let’s arrange the steps of the scientific method in order… The Scientific Method

Quantitative Data

Qualitative Data

A hypothesis is an educated guess that predicts the results of your experiment, dictates what you will test and forms the limits of the experiment.

Experimental Group & Control Group

The purpose of the control group during an experiment is to have something to compare your data to (baseline data).

Independent & Dependent Variable

Measuring heart rate changes (bpm), plant growth (cm), bacterial colony growth, etc.

Daphnia exposed to caffeine

Daphnia not exposed to caffeine

The purpose of constants are to ensure that the experiment is testing only the independent variable’s affect on the dependent variable.