1. https://youtu.be/nSENolWbyYQ
Unit 2 The Earth’s Water

2. I. Lesson 1 Water and Its Properties A. Water’s roles on Earth
Water facts:
You are % water
Only 3% of all the water on Earth is drinkable
Of that 3%, 75% of the drinkable water is locked away in polar ice caps

3. Influencing weather https://youtu.be/moSBExlLu2M
Water constantly moves throughout the Earth’s atmosphere and back to the surface of the Earth
Water Shapes the Earth’s surface
Erosion and deposition
Water supports life
Body uses water to transport oxygen and nutrients in our blood stream
Plants need water to grow

4. Human activities Bathing, cleaning, watering lawns & gardens
20% of human water usage is for manufacturing goods, cool power stations, hydroelectricity (dams)
Irrigate crops
Water livestock

5. B. States of water Three states of water= solid, liquid, gas
When water changes from state to state it releases energy
Molecules are tightly packed in a solid state
Molecules have more room for movement in a liquid state
Molecules are far apart in the gaseous state
Water expands when it freezes trapping air making it less dense than water

6. C. Molecular attraction of water https://youtu.be/ASLUY2U1M-8
Water consists of 2 hydrogen atoms & 1 oxygen atoms (making the shape of Mickey Mouse)
Polarity= having a positive charge at one end and a negative charge at the other end
The oxygen end has a negative charge and the hydrogen has a positive charge

7. D. The Universal Solvent: 4 properties of water https://youtu
Cohesion: property that holds molecules of a substances together
Water sticks to itself
Reason water forms drops
Insects can walk on water
Adhesion: property that holds molecules of different substances together
Capillary action: water “sticks” to another substance and moves up into that substance
Ex: water and papertowel

8. Specific heat: energy needed to heat a substance by a particular amount
Specific heat of water is very high
Allows water to store energy (heat) & to release energy (heat)
Important for Earth’s climate & weather
Water is the Universal Solvent: dissolves ALMOST anything given enough time
Water dissolves and transports minerals, nutrients and oxygen in our blood to transport them to cells
Can dissolve rock over time (Grand Canyon)