Also called glycerin or glycerine, Glycerol is both a colorless and odorless liquid, that is fairly viscous. It is a simple polyol compound, with a triglyceride backbone and 3 hydroxyl groups.
Cobalt chloride crystals are commonly used in classrooms for chemistry experiments and demonstrations, primarily to study chemical properties and investigate reactions involving moisture and hydration. The most notable uses include:
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Indicator for Humidity and Hydration: Cobalt chloride is a popular indicator for moisture because it changes color based on its hydration state. In its anhydrous form, cobalt chloride is blue, and it turns pink when it absorbs water. This property makes it ideal for demonstrating reversible chemical changes and teaching about hydration and dehydration reactions.
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Le Chatelier’s Principle Demonstrations: Cobalt chloride can be used to illustrate Le Chatelier's Principle. By adding water or applying heat to the crystal, students can observe the reversible color change, demonstrating shifts in equilibrium due to changes in temperature or the presence of a reactant.
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Testing for Water Presence: Cobalt chloride paper, which is made using the crystals, is used in chemistry and environmental science labs to detect water vapor in various gases or liquids.
Due to its potential toxicity and the fact that it can cause skin irritation, cobalt chloride should be handled with proper safety measures, including wearing gloves and protective eyewear.
Sodium acetate, lab grade, anhydrous, powder - 500g.
Silver nitrate solution (0.1 normal) is used in classrooms for various chemistry experiments, particularly for demonstrating precipitation reactions and studying properties of silver ions. It is commonly used in:
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Precipitation Reactions: When silver nitrate is mixed with solutions containing chloride ions (e.g., sodium chloride), it forms a white precipitate of silver chloride. This reaction is useful for teaching concepts like solubility rules and ionic equations.
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Halide Testing: It can be used to identify halides (chloride, bromide, and iodide ions) in solutions, as each halide forms a distinct precipitate color (white, cream, or yellow) with silver nitrate.
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Titration Experiments: In analytical chemistry, a 0.1N silver nitrate solution can be used for Argentometric titrations, such as the Mohr method, to determine the concentration of chloride in a sample.
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Biological Staining and Antimicrobial Studies: In some biology classes, silver nitrate is used for staining, and its antimicrobial properties can be demonstrated to show how it affects microbial growth.
Because silver nitrate can stain skin and other materials, safety precautions such as gloves and goggles should be used when handling it.
Limewater solution is commonly used for testing the presence of carbon dioxide in gaseous samples in school laboratories, and refining of sugar in a process called carbonatation. 4 liters.
Limewater solution is commonly used for testing the presence of carbon dioxide in gaseous samples in school laboratories, and refining of sugar in a process called carbonatation. 1 liter.
2,6-Dichloroindophenol Sodium salt (indophenol), reagent - 1g
Non-nutrient agar powder is typically used in classrooms for microbiology experiments, such as studying slime molds, observing fungal growth, or culturing environmental samples. Since it lacks nutrients, it does not support the growth of most bacteria or fungi on its own, making it ideal for experiments where a nutrient source is added selectively to encourage the growth of specific organisms. It's often used to highlight the effects of environmental factors on microbial growth, demonstrate the role of external nutrient sources, or as a base for investigating other biological processes.
Tin Metal, lab grade, mossy - 100g.
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.
Potassium Iodide, lab grade, granular - 25g.
