Safety and Scientific Method

Lab Rules Use only the equipment and materials required for your lab Read directions Wear your goggles Think and act safely Stay at your station unless materials are needed or there is an emergency Clean up and return all materials

Lab Safety Safety rules are found in your text and on a handout. You have been quizzed over the rules and you must pass the quiz in order to participate in lab activities.

Lighting your Bunsen burner Turn the knob on the burner so that it is not completely closed Be sure gas connection is good Light the match Turn on the gas

Turning off your burner Turn off the burner at the gas source, not at the burner When the handle is perpendicular to the gas jet, the gas is off.

NEVER, NEVER Never throw matches in the sink! Put them on the table. Later, when cool, or after wetting, throw them in the trash.

Lab Equipment Identify each of the following: flask Screen and burner microscope beaker Test tubes and rack

clamp ring Ring stand Wire screen Erlenmeyer flask Magnifying glass

Florence flask Erlenmeyer flask Graduated cylinder

15 16 Electronic scale chicken

What belongs in my lab drawer? Goggles- 2 or 3 pair Wire screen Bunsen burner Test tube holder Test tube brush Tongs Test tube rack (this belongs in the cubby above your drawer)

Scientific Method State the problem Gather information Form a hypothesis Test the hypothesis Record and analyze data State a conclusion Repeat the work

Controls and Variables Only one variable in an experiment It is important to control all other factors

Inferences & Observations Observation = anything taken in through the senses (see, hear, taste, smell, touch, or taste) Observation = anything taken in through the senses (see, hear, taste, smell, touch, or taste) Inference = statement that explains the observations or conclusion based on observations Inference = statement that explains the observations or conclusion based on observations Ex: Suppose your friends went to the beach at noon on a warm day and saw some black and white birds. Which of the following are observations and which are inferences? Ex: Suppose your friends went to the beach at noon on a warm day and saw some black and white birds. Which of the following are observations and which are inferences?

1. It is summertime. 2. It is day time. 3. They saw birds. 4. They saw seagulls. 5. They went swimming. 6. One friend’s name was Bob. 7. It was a warm day. 8. The birds were black and white. 9. They ate lunch and drank Coke. 10. The people are friends.