Unit 2: Particle Theory of Matter
Ms. Kwon put water in the freezer. Later, she took out an ice from the freezer. It melted on a table and later it disappeared! Name three changes of state that happened in order.
freezing, melting, evaporation
What is an “ecosystem”? Give an example of an ecosystem.
where living things interact with other living things and non-living things (e.g., tropical rainforest, desert)
Name the four Earth’s layers in order from HOTTEST TO COLDEST.
Inner core, outer core, mantle, crust
What are the three types of structures? Describe and give an example for each.
-solid: filled inside, usually heavy (e.g., brick)
-frame: made up of small parts (e.g., umbrella)
-shell: empty inside (e.g., fish tank)
A homogeneous matter that consists of only one type of particles is called… (and give an example of it)
pure substance (e.g., water, gold)
Describe two abiotic-biotic interactions.
-ants making a home inside the soil
-fish living in water; animals breathing oxygen to survive
What are minerals and what are rocks? Give an example of each one.
-Mineral: Solids that occur naturally on the Earth (e.g., diamond, gold)
-Rock: made up of one or more minerals (e.g., igneous rock, granite)
If you sitting on a chair. Name two forces that are acting on you (and in which direction they are pulling you).
-gravity = pulling you down
-internal force/supporting force of chair= pushing you up
Name two examples homogeneous mixtures and two examples mechanical mixtures (heterogeneous mixtures).
Homogeneous (tea, juice)
Heterogeneous (salad, pizza)
What is the main difference between a producer and a consumer? Give an example for each one.
-producers make their own food (e.g., algae, plants) while consumer can’t and have to consume/eat other organisms to survive (e.g., mouse, humans)
What is “erosion”? How can plants prevent erosion from happening?
Weathered rocks (broken down rocks) moving by natural forces
-plants' roots grow into the soil and hold them together, preventing it from being washed away
What is the difference between a dead load and a live load? Give an example for each.
-dead load: weight of the structure itself (e.g., chair weighing 10 kg)
-live load: weight inside or on a structure (e.g., cars)
Daniel placed a balloon in a hot place. What might happen to the balloon? And give reasons why this might happen in terms of the particle theory of matter.
-balloon might expand, pop
-particles move faster & move further apart at higher temperatures, making them hit the surface of the balloon
Let’s assume that the animals in an ecosystem only eat one thing: grass->grasshopper->frog->python->eagle. Imagine the frogs all died. What will happen to each organism?
Grass: decrease
Grasshoppers: increase (later decrease)
Python: decrease
Eagle: decrease
Give an example of physical / chemical / biological weathering.
physical: ice expanding rock, wind blowing
chemical: limestone caves, acid from lichen & moss
biological: prairie dogs, moss & lichen
Describe the difference between structural stress/fatigue/failure. Give an example for each one.
-stress: you sitting on a chair
-fatigue: a wall having cracks
-failure: house breaks down
Name three statements from the Particle Theory of Matter.
-All matter is made up of particles
-Particles are always moving
-Particles are attracted to each other.
-Each pure substance is made up of only one type of particle.
-Particles at a higher temperature are moving faster than particles at a lower temperature.
What is photosynthesis? What is cellular respiration? Write the equation for photosynthesis & cellular respiration.
-photosynthesis: how producers make their own food (water+CO2+sunlight -> sugar(food) + O2)
-cellular respiration:how living things release energy stored in food (sugar + O2 -> CO2 + water+ energy)
What are the three types of rock? How is each one formed?
-igneous: when magma or lava cools
-sedimentary: sediments harden over years
-metamorphic: high heat & pressure underground
Name the four internal forces. Give an example for each one.
-tension: pulling a rope
-compression: pressing a sponge
-torsion: twisting a towel
-shear: cutting/tearing paper