3. Most of Earth’s water is salt water. 97% of Earth’s water is in the oceans and is too salty to drink.
4. Most of Earth’s water is salt water. 97% of Earth’s water is in the oceans and is too salty to drink. The remaining 3% is fresh water in rivers, lakes, aquifers, glaciers, rain, snow and vapor (clouds).
5. How much of Earth’s surface is covered with ocean?
15. Liquid water that is in a sealed container stays there. But water that is open to the air seems to disappear in a few hours or days. Rain on the sidewalk “dries up” in an hour or two after the rain stops. When water turns into vapor this way it is called
16. Liquid water that is in a sealed container stays there. But water that is open to the air seems to disappear in a few days. Rain on the sidewalk “dries up” in an hour or two after the rain stops. When water turns into vapor this way it is called evaporation .
17. When water evaporates it slowly vaporizes into a gas and becomes part of the air around us. Sometimes we can see this vapor as fog or clouds in the sky but it’s usually invisible unless the water is boiling.
18. Water vaporizes quickly when it gets hotter than 212 degrees Fahrenheit (100 degrees Celsius). When water is boiling you can see it forming bubbles of gas called steam.
23. You can also see condensed vapor when drops of water form on the outside of a cold drink glass.
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25. What happens to water when it gets colder than 32 degrees Fahrenheit (0 degrees Celsius)?
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31. The world has a limited amount of fresh water in rivers, lakes and glaciers. People need to save water wherever they can. Even a leaky faucet wastes a lot of water over time.
42. Its round shape. unlight Sunlight hits the equator directly but glances but at the curved top and bottom bot of our planet rays are spread out. round
43. The Earth gets more heat at the equator than it does at the north and south regions. What does this uneven heating cause?
44. The Earth gets more heat at the equator than it does at the north and south regions. What does this uneven heating cause? Air movements (Wind currents.)
48. What could happen when a cold current mixes with a warm current ? A heavy storm can develop when cold and warm masses collide.
49. What kind of weather will happen where the weather map has a big “L” indicating a low pressure system?
50. Low pressure “L” means unsettled, possibly stormy weather. A high pressure “H” means the weather should be nice.
51. Which elevation would have less air pressure, the beach (0 feet altitude) or a mountain top (5,000 feet altitude) ?
52. Elevation is measured from sea level which is considered zero elevation. The higher you go (bigger elevation number) the less air pressure there is.
53. At sea level the elevation is zero and air pressure is about 14 pounds per square inch.
54. The air gets thinner (it’s harder to breathe) the higher you climb on a mountain. The highest mountain is 29,000 feet high.
55. Jet airplanes fly at about 35,000 feet where the air is too thin to support life. High flying jet cabins are pressurized, otherwise oxygen masks would be needed to keep people alive.
62. How big is the Sun compared to Earth? Much bigger
63. How big is the Sun compared to Earth? Much bigger It the Sun were a basketball, Earth would be a grain of sand.
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65. Why do planets appear at different places in the sky from week to week while the stars all stay in the same places in relation to each other?
66. Why do planets appear at different places in the sky from week to week while the stars all stay in the same places in relation to each other? The planets orbit the Sun at different rates of speed.
67. Why do planets appear at different places in the sky from week to week while the stars all stay in the same places in relation to each other? The planets orbit the Sun at different rates of speed. It’s like kids playing at a park. The trees stay in the same place but the kids move to different places.
