Pollution and Microplastics
How big are microplastics?
5mm and smaller / Less than 5mm
What is the difference between natural and synthetic materials?
Natural materials occur in the world without human intervention
Synthetic materials need to be made by people, usually with at least one chemical reaction
What does the suffix -thermic mean?
What do the prefixes endo- and exo- mean?
-thermic: related to heat
endo- : into / inside
exo- : out of / outside
11. What value on the pH scale represents a neutral pH?
7
17. List the three different types of heat transfer
Conduction, convection, and radiation
1. Name the six main types of pollution.
Air, Water, Soil, Noise, Light, Radiation
3b. Do natural and synthetic materials tend to decompose at the same rate?
No, synthetic materials usually take much longer.
5. What happens during a physical change? Give an example of a physical change.
A physical change occurs when an object changes (like being torn, bent, molded, etc.) without changing what that object is.
Ex: Tearing a piece of paper; melting an ice cube
12. What values on the pH scale represent acidic substances?
Anything below 7
18. Which type of heat transfer only occurs via direct contact between two objects?
Conduction
2b. What happens to the volume of the plastic after a water bottle breaks down into microplastics?
The volume stays the same.
3c. Give three examples of natural materials
Wood, stone, clay, cotton, etc.
6. What happens during a chemical reaction? Give an example of a chemical reaction.
During a chemical reaction, a change in an object occurs that also changes what that object is.
Ex: Burning wood into ash; Mixing aluminum and iodine to produce aluminum triiodide
13. What values on the pH scale represent basic (alkaline) substances?
Anything above 7
19. Which type of heat transfer only occurs through fluid (liquid or gas) objects?
Convection
2c. What happens to the surface area of the plastic after a water bottle breaks down into microplastics?
The surface area increases.
3c. Give three examples of synthetic materials
Plastic, steel, nylon, polyester, styrofoam, etc.
9. What happens during an endothermic reaction?
10. What happens during an exothermic reaction?
9. Heat/thermal energy is absorbed
10. Heat/thermal energy is released
14. Give two examples of acidic substances
15. Give two examples of basic (alkaline) substances
14. Soda, citrus, gastric acid, coffee, vinegar, etc.
15. Bleach, baking soda, soapy water, etc.
20. Which type of heat transfer can occur through solids, fluids, and even vacuums?
Radiation
2d. Why are microplastics dangerous? Give 3 reasons.
1. Microplastics travel up the food chain
2. Microplastics provide a lot of surface area for harmful bacterial colonies to grow
3. Microplastics absorb and concentrate toxic chemicals
What are your variables and constants in the following experiment:
You are performing a test to see what color light will cause plants to grow more quickly. You start with four pea plants that are all the same height. The first plant is exposed to normal sunlight. The second plant is exposed to red light only. The third plant is exposed to blue light only. The fourth plant is exposed to green light only. All four pea plants are exposed to their respective lights for 14 hours every day, and then 10 hours of darkness every day. Each plant receives the same amount of water and fertilizer, and all of the lights are the same brightness. You are measuring the height of the plants every week for two months.
IV: The color of light the plants are exposed to
DV: The height of the plants
Constants: The amount of water given to each plant, the amount of fertilizer given to each plant, the plant species tested, the brightness of the light each plant is exposed to, the amount of time each plant is exposed to light, etc.
What kind of reaction is this?
2Fe2O3 + 3C + heat → 4Fe + 3CO2
Endothermic
16. Describe what a pH buffer does and give an example of one
A pH buffer neutralizes both acids and bases, this means that it will bring their pH closer to 7.
Ex: chalk, tums
Give an example of each of the three types of heat transfer: Conduction, Convection, and Radiation
Answers may vary