Water is vital to all life on Earth and covers nearly three-fourths of our planet's surface. Where does it come from? Will we use it up eventually? In The Water Cycle, students learn that Earth has the same water supply today as it did millions of years ago. Examine the amazing process by which water is continually recycled and transported from place to place through evaporation, condensation and precipitation. Also find out how energy from the sun drives the water cycle and how the atmosphere prevents water from slipping away from Earth. A fun, hands-on investigation demonstrates how an artesian well works, while a visit to a desalination plant showcases how salt water is purified. Part of the Earth Science in Action DVD Series. A Teacher's Guide is included and available online. 23 minutes. Grades 5 to 8.
Ideal field test kit for performing 4 important experiments on water pollution. Test water samples for dissolved oxygen content, chlorides, phosphates, and water hardness. This kit provides all the apparatus and materials necessary for performing each test several times. Comes complete with instruction booklet.
Weather affects everyone, everyday! Introduce Isobars, Jet Streams, Wind Chills and more with this super-sized 44" W x 20" H weather map of the U.S. and Canada. Chart temperatures and cities using bar and line graphs. Write-on/ wipe off board with grommets for easy display, conveniently folds flat. Teacher's guide with weather terms, activities, vinyl cling weather symbols and student recording charts included. Grades 3-8.
The rocks and soil that make up Earth's surface are constantly being affected by a variety of forces, ranging from heat and frost to water and wind. In Weathering and Erosion, students will discover the natural forces that cause weathering, erosion and deposition, and see the many effects that these processes have on Earth's surface. Students will examine natural structures around the world and see how weathering and erosion have affected them, while discovering ways in which people have become better prepared to battle these forces through conservation. In addition, a fun, hands-on experiment demonstrates how running water erodes different types of soil. Part of the Earth Science in Action DVD Series. A Teacher's Guide is included and available online. 23 minutes. Grades 5 to 8.
• Made with 0.35mm thick PVC and polyester fabric
• Detachable hood with drawstring
• Storm flap front with snap closure
• 2 flapped front pockets with snap closures to secure valuables
• Cape vented back
• Corduroy collar for comfort
• Available in 4 Sizes
• Available with or without CROSSING GUARD Emblem on Back
This bright yellow rain jacket is made of tough .35mm PVC and polyester fabric. Corduroy lined collar for comfort. Coat has cape-vented back . Includes detachable hood.
| Chest | Length | Sleeve | |
| Medium | 56 in. | 30.5 in. | 32 in. |
| Large | 58 in | 31.5 in. | 33 in. |
| X-Large | 60 in. | 32 in. | 34 in. |
| 2X-Large | 62 in. | 33 in. | 35 in. |
This chart has illustrations and actual specimens for students to consult as they identify unlabeled rock specimens. For grades 6-12. 23 1/2" x 15 1/5".
For use with 12046 What Rock Is It? classroom project.
A highly detailed eye model to satisfy beginning students. Dissectible into 7 parts that include: top section, vitreous body, bottom section, lens (2 parts), iris, cornea. Mounted on a stand. Includes keycard with 41 structures labeled. Enlarged 6 times. Size 5 1/2" x 6 1/4"
These polypropylene bottles are rigid, translucent and have excellent contact clarity. These bottles can be autoclaved filled as well as empty. The polypropylene cap has a built-in seal ring to make these bottles leak proof.
| Size | Height | Neck Diameter ID/OD |
Pack Size |
| 60ml | 73mm | 20mm / 25mm |
Pack of 12
|
| 125ml | 100mm | 27mm / 32mm |
Pack of 12
|
| 250ml | 137mm | 35mm / 41mm |
Pack of 12
|
| 500ml | 149mm |
35mm / 41mm |
Pack of 12
|
|
1000ml
|
218mm |
35mm / 41mm |
Pack of 6
|
The perfect way to alert the public to hazards that are located in unlit or dimly lit areas. This highly visible tape comes with a liner.
Zinc metal, foil 0.010" x 12" x 36", (1 piece = 500g) - 500g
Zinc metal, foil 0.010" x 12" x 36", (1 piece = 500g) - 500g
Zinc sulfate, lab grade, granular is commonly used in classroom settings for chemistry experiments and to illustrate various scientific concepts due to its solubility and reactivity. Some of the typical applications include:
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Precipitation Reactions: Zinc sulfate is used to demonstrate precipitation reactions when mixed with other compounds. For example, when combined with sodium carbonate, it forms zinc carbonate, a white precipitate. This can be used to illustrate the principles of solubility, ionic reactions, and compound formation.
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Galvanic Cells and Electrochemistry: Zinc sulfate is frequently used in electrochemical cells (such as Daniell cells) to study the behavior of zinc as an electrode and to teach concepts of oxidation and reduction, electrode potentials, and electron flow in galvanic cells.
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Testing for Anions: It can be used as a reagent in testing for the presence of specific anions in solutions. For instance, in analytical chemistry, zinc sulfate might be utilized in qualitative tests to help identify sulfide ions through the formation of a white precipitate (zinc sulfide).
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Growth Medium for Biological Studies: In biology and environmental science classes, zinc sulfate is sometimes used as a trace element in preparing growth media for certain plants or algae to study the effects of zinc on growth and development.
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Illustrating Properties of Transition Metals: Zinc is often grouped with other transition metals to compare chemical properties, such as reactivity with acids and the formation of complex ions in solution.
Safety precautions should be observed when handling zinc sulfate, as it can be harmful if ingested or inhaled in powder form. Proper protective equipment, such as gloves and safety goggles, is recommended during use.