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Topic : Scientific Method Aim : Explain the difference between observations and inferences. Do Now : Explain the difference between the - independent and dependent variables - experimental and control group HW : Study for lab safety quiz Sign on to Castle Learning. Let ’ s summarize…
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Topic: Scientific Method Aim: Explain the difference between observations and inferences. Do Now: Explain the difference between the - independent and dependent variables - experimental and control group HW: Study for lab safety quiz Sign on to Castle Learning
Let’s summarize… Identify the improper lab procedure observed in the diagram.
Independent variable = ? SUNLIGHT
To investigate how temperature affects seed germination (the sprou, a student placed 10 radish seeds of the same variety on moist paper in each of 3 petri dishes and placed the dishes in the following environments: Dish # 1: Refrigerator, 5ºC Dish # 2: Room Temperature, 20ºC Dish # 3: Incubator, 37ºC 1. Identify the problem. 2. Identify the control group. Support your answer. 3. Identify the independent and dependent variables. 4. Identify TWO factors that must remain constant (2 CONTROLS). 5. What must be done to make the results of this experiment more valid.
What do you use when making observations? • One or more of your senses • Sight, hearing, smell, taste, touch
Describe an accurate and objective observation. • Sixteen students were present for roll call, and five other students arrived afterward.
Identify the two types of observations. • Qualitative and quantitative
Identify the type of observation that DOES NOT use numbers . • Qualitative • Using your senses • EX: • The classroom walls are yellow. • The classroom floor is shiny.
Identify the type of observation that DOES use numbers. • Quantitative • Ex: • There are 21 students in the room. • The chalkboard is 1 meter high and 2 meters wide.
Describe what an interference is. • A statement explaining or interpreting an observation or statement. • Ex: • Observation: The cattle and the antelope are standing quietly together. • REASONABLE Inference: The cattle and antelope do not attack each other. • Ex: • Observation: Some of the cattle are eating grass. • REASONABLE Inference: The grass is food for the cattle and antelope.
How can an unreasonable inference be made? • By concluding too much from the evidence. • Ex: • Observation: The cattle and the antelope are standing quietly together. • UNREASONABLE Inference: None of the animals in this region attack each other • Ex: • Observation: Some of the cattle are eating grass. • UNREASONABLE Inference: Most of the grass in this area is eaten by the cattle.
Observation or Inference??? • My hands are getting warm. • Friction or heat is produced while rubbing my hands. • We smell the fragrance of the perfume. • The lights are off because no one is home. • Air molecules travels around the room. • The mouse is scared. • The animal has 4 legs.
True or False? It is ok to dump a chemical down the sink.
True or False? If any glassware breaks, the student should clean it up right away.
True or False? Perform only those experiments for which you have been instructed.
True or False? It is ok to joke around and run around the room when performing a lab.
True or False? You must not touch any equipment or chemicals unless instructed to do so by your teacher.
True or False? If a piece of laboratory equipment breaks, you just leave it there for the teacher to see.
True or False? You do not have to tie your hair back when working with chemicals.
True or False? When smelling a chemical, use the wafting technique.
True or False? Yanking the cord is the proper technique to use when unplugging electrical equipment.
True or False? All equipment must be carried with two hands.