Observation vs Inference
What do you call something you can see, hear, smell, taste, or touch?
What is an observation?
What should you always wear to protect your eyes in the lab?
What are goggles?
What are the three main states of matter?
Solid, Liquid, Gas
Which tool measures liquid volume?
Graduated Cylinder
True or False: An inference can be wrong.
True
You see smoke and say, “There must be a fire.” Is that observation or inference?
What is an inference?
You accidentally spill water near a computer. What should you do first?
Tell the teacher immediately.
What happens to the particles of matter when a solid melts?
They move faster and slide past one another.
Which unit is used to measure mass in science class?
What are grams?
You see frost on the grass. You say, “It must have been cold last night.” Is that observation or inference?
Inference
You see a student yawning. You say, “They stayed up too late.” Which part is the observation, which is the inference?
Yawning = observation; Stayed up too late = inference
Why should you never eat or drink in the science lab?
To avoid accidentally ingesting chemicals or harmful substances.
What is the difference between a physical change and a chemical change?
Physical = changes form but not identity; Chemical = makes a new substance.
If you need to measure temperature, what tool would you use?
thermometer
Why do scientists record observations carefully during an experiment?
So they have accurate data to analyze and compare.
Why is an inference more like a guess than an observation?
Because it’s an explanation or conclusion based on evidence, not a direct fact from the senses.
You see smoke coming from a beaker. A student grabs it to move it. What rule did they break?
Never touch hot glass or materials without permission.
Ice cubes are left out and turn into liquid water. Is this a physical or chemical change, and why?
Physical, because it’s still water (H₂O).
Why is it important to use the metric system in science?
So scientists everywhere use the same standard units.
A candle burns and produces black smoke. What are TWO observations you can make?
Examples: flame is orange, wax is melting, smoke is black, it is hot.
You walk into the cafeteria and see trays full of pizza. Someone says, “It’s Pizza Friday.” What is the observation and what is the inference?
Observation = trays full of pizza; Inference = It’s Pizza Friday
Explain why “horseplay” is dangerous in a science lab.
Because it can lead to accidents, spills, or injuries with dangerous materials.
A nail rusts when left outside. Identify the evidence that this is a chemical change.
Rust is a new substance with different properties than the nail.
What is the difference between a triple beam balance and an electronic scale?
A triple beam balance measures mass manually; an electronic scale gives a digital measurement.
You measure a rock and note it weighs 250 grams and is gray in color. Which part is a quantitative observation and which is a qualitative observation?
250 grams = quantitative; gray color = qualitative.