Physical & Chemical Changes
Electricity and magnetism
Constructive and destructive forces
cells and microorganisms
Inheritance and classification
100
What is a physical change ?
what is a physical change? A physical change is a change that doesn't create a new substance.
100
💡 Question: What is the difference between a conductor and an insulator? (Choose the correct answer.)
A conductor lets electricity flow, and an insulator stops electricity.
100
What is a constructive force?
What is a constructive force? A constructive force is a beneficial force that can build up and create new landforms.
100
What is a microorganism?
What is a microorganism? A microorganism is a tiny living organism that can only be seen under a microscope. Examples include bacteria, fungi, protozoa, and viruses.
100
What is an amphibian? What all does an amphibian have?
What is an amphibian ? what all does it have? Answers : Cold blooded, live near water, smooth, moist skin, lays eggs in water.
200
What happens when salt dissolves in water? Does this change its chemical composition?
Salt dissolves in water by breaking into smaller particles (ions) that spread throughout the liquid.
No, the chemical composition of salt (NaCl) does not change; it is still salt, just mixed into the water.
200
💡 Question: You tested a metal spoon and a wooden spoon in a circuit. The light bulb turned on with the metal spoon but not the wooden one. Why?
✅ Answer: The metal spoon is a conductor, so it lets electricity flow. The wooden spoon is an insulator, so it stops electricity.
200
What is a destructive force ?
What is a destructive forces? A destructive force is a force that can be harmful and beneficial to earth
200
Compare beneficial and harmful microorganisms.
Beneficial microorganisms help with processes like digestion, food production, and decomposition. Harmful microorganisms can cause diseases and spoil food. For example, E. coli can be harmful, while Lactobacillus is beneficial.
200
What is an inherited trait? What is an acquired trait?
What is an inherited trait? What is an acquired trait?
An inherited trait is a physical characteristic passed down from parents to their offspring through genes.
Example: Eye color, hair type, dimplesAn acquired trait is a physical characteristic a person develops over time due to environment, experience, or lifestyle.
Example: Scars, dyed hair, muscles from exercise
300
If you freeze water into ice and then melt it back into water, how do the properties of the substance change or stay the same?
The state of matter changes (solid to liquid and back), but the chemical composition of Hâ‚‚O remains the same.
300
What is a permanent magnet?
What is a permanent magnet?
A permanent magnet is a magnet that maintains its magnetic properties without needing an external electric current.
300
How can a destructive force be beneficial to earth?
A destructive force can be beneficial to earth, by if a volcano erupts after the eruption is over, the volcano would create new landforms .
300
Explain how yeast is used in baking and why it's considered beneficial.
Yeast, a type of fungus, feeds on sugars and produces carbon dioxide gas, which helps dough rise. It’s beneficial because it makes bread light and fluffy and contributes to fermentation in food and beverage production.
300
How is an inherited trait different from an acquired trait? Can you give an example of each?
Difference: Inherited traits come from your parents and are present at birth. Acquired traits are gained after birth through experience or environment.
Inherited trait: Naturally curly hair
Acquired trait: A pierced ear
400
Develop a step-by-step procedure for separating a mixture containing sand, salt, and iron filings. Justify why you chose each separation method and how it demonstrates physical changes.
Step 1: Use a magnet to remove the iron filings (magnetism).
Step 2: Add water to the sand and salt mixture. The salt will dissolve while the sand remains.
Step 3: Use filtration to separate the sand from the saltwater solution.
Step 4: Evaporate the water to retrieve the salt.
Justification: Each step relies on a physical property (magnetism, solubility, and evaporation) without changing the chemical composition of the materials.
400
Define temporary magnetism.
Temporary magnetism occurs when a material becomes magnetized only while an external force, such as an electric current, is applied.
400
Give an examples of constructive force features.
A crack starts to grow over the years and forms a canyon after many years of growth including color and shades.
400
Using at least two pieces of scientific evidence, construct an argument that supports the claim that some microorganisms are beneficial to human health.
Many microorganisms are essential to human health. For example, gut bacteria like Bifidobacterium help digest food and produce vitamins such as B12. Studies show that probiotics can improve digestion and strengthen the immune system. Therefore, not all microorganisms are harmful; some are vital for our well-being
400
Is writing with a certain hand (left or Right ) an acquired trait or inherited? Explain your answer.
Inherited because my mom and dad right with their right like me.
500
Create a model or simulation to show how mixtures can be physically separated using different techniques like filtration, magnetism, and evaporation. How could this knowledge be useful in environmental science or industry?
Model: Use different materials (iron filings, sand, salt, water) to create a hands-on demonstration of separation techniques.
Application in environmental science: Cleaning polluted water by filtering out impurities.
Application in industry: Separating useful materials in mining and recycling.
500
List two materials that can be used to create an electromagnet.
Iron and steel.
500
What is erosion?
What is erosion? Erosion is moving land or soil, by the action of wind, water, or ice.
500
Design an investigation or multimedia presentation that presents an argument, supported by scientific evidence, showing how microorganisms can be used in environmental cleanup efforts (e.g., oil spill bioremediation).
[Sample project idea] Students could create a video presentation explaining how certain bacteria, like Pseudomonas putida, are used to break down oil in marine environments. The presentation would include data from case studies (e.g., the Deepwater Horizon spill) and interviews or quotes from environmental scientists, showing how these microbes reduce pollution and support ecosystem recovery.
500
Give an example of an acquired trait.
An example of an acquired trait could be legs.