Year 8 Science · Unit 2 · Lesson 06
Challenge Worksheet
Learning Goals
Design a mini-experiment
A scientist wants to test: "Does the number of protons in an atom determine what element it is?" Plan the investigation below. Imagine you have access to a particle detector that can count protons inside atoms of unknown samples.
| What I will change (independent variable) | |
| What I will keep the same (controlled variables, list 3) | |
| What I will measure (dependent variable) | |
| My prediction | |
| How I would know if my prediction is wrong (falsification condition) | |
| One limitation of this experiment |
1. If you removed one proton from a gold atom (which has 79 protons), what element would you have? Use a periodic table if available. What does this tell you about what makes an element an element?
2. Scientists at ANSTO (Australian Nuclear Science and Technology Organisation) use particle accelerators to study atomic nuclei. If they fired a beam of particles into a carbon atom and knocked out 3 neutrons but left the protons untouched, would the result still be a carbon atom? Explain your reasoning using what you know about protons, neutrons and atomic identity.
Wrap Up
In one sentence, what was the main idea of this lesson?