How to use C.E.R. for experiments & Labs Claim, Evidence, & Reasoning

Claim, Evidence, Reasoning Claim, Evidence, and Reasoning or C.E.R is a strategy that we will be using when we perform experiments and labs.

C.E.R CLAIM: A statement about the solution to a problem. EVIDENCE: Scientific data that supports the claim. REASONING: Justification (which means you have to back it up) that shows why the data counts as evidence which supports the claim.

What? Still Confused?

Consider This! Your teacher asked the following key question for a class lab experiment: Would a new color result from mixing yellow and blue? You and your lab partner performed the lab experiment, where you mixed yellow and blue food coloring --the result, was green.

Your C.E.R may look something like this: Key Question: Would a new color result from mixing yellow and blue together? Hypothesis: If I mix colors together then a new color will result. C: When blue and yellow is mixed the result color will be green.When yellow and blue are mixed together they make the color green. The claim answers the question and makes a statement from the hypothesis.

E: 10 ml of yellow food coloring was measured and mixed with 10 ml of blue food coloring which resulted (you ended up with) 20 ml of green food coloring. Three identical tests were done and they all resulted in green.

R: Observations were used to see that when yellow and blue were mixed together they made green. The fact that the experiment was done 3 times means that it is reproducible and accurate. Two different colors when mixed together do make a new color.

Still Confused?

How do you make slime? Hypothesis: IF I mix water, glue, and mystery powder (borax) together, THEN I will make a new substance (slime). C: Combining glue, water, and mystery powder caused a chemical reaction which resulted in a new substance called slime.

E: I observed that a new substance was made because the substance that was created had very different properties from the original substances. Some of the new properties were: color change, texture change, cannot be separated, and it bounced. R: I know that it made a new substance because I did the experiment. I believe it is a chemical change because it cannot be reversed. I observed all the changes myself and because other classmates did the same experiment with the same results it can be considered reliable and reproducible.

What is the question/problem you want to answer? What is the source for the evidence you will use to support your explanation? (name of lab, activity, text, movie…. List those here) Claim – What do you think answers the question/problem? Evidence that supports your claim (list it, be specific, use data when available) Reasoning: I think (insert your claim here) answers the question because (links evidence to the claim).

Let’s Try This Together See handout

Let’s look at this simple flow chart What is the Claim?What is the Question I want to ask? What evidence would I accept to support the claim ( how should I set up an experiment to test the claim)? What evidence did I actually get?