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  2. Chalk - Wikipedia

    en.wikipedia.org/wiki/Chalk

    Chalk is so common in Cretaceous marine beds that the Cretaceous Period was named for these deposits. The name Cretaceous was derived from Latin creta, meaning chalk. [10] Some deposits of chalk were formed after the Cretaceous. [11] The Chalk Group is a European stratigraphic unit deposited during the late Cretaceous Period.

  3. List of alchemical substances - Wikipedia

    en.wikipedia.org/wiki/List_of_alchemical_substances

    Lye – potash in a water solution, formed by leaching wood ashes. Potash – potassium carbonate, formed by evaporating lye; also called salt of tartar. K 2 CO 3; Pearlash – formed by baking potash in a kiln. Milk of sulfur (lac sulphuris) – formed by adding an acid to thion hudor (lime sulfur). Natron/soda ash/soda – sodium carbonate ...

  4. Calcium carbonate - Wikipedia

    en.wikipedia.org/wiki/Calcium_carbonate

    Water in aquifers underground can be exposed to levels of CO 2 much higher than atmospheric. As such water percolates through calcium carbonate rock, the CaCO 3 dissolves according to one of the trends above. When that same water then emerges from the tap, in time it comes into equilibrium with CO 2 levels in the air by outgassing its excess CO ...

  5. Chemical reaction - Wikipedia

    en.wikipedia.org/wiki/Chemical_reaction

    Nuclear chemistry is a sub-discipline of chemistry that involves the chemical reactions of unstable and radioactive elements where both electronic and nuclear changes can occur. The substance (or substances) initially involved in a chemical reaction are called reactants or reagents .

  6. Glossary of chemistry terms - Wikipedia

    en.wikipedia.org/wiki/Glossary_of_chemistry_terms

    Also acid ionization constant or acidity constant. A quantitative measure of the strength of an acid in solution expressed as an equilibrium constant for a chemical dissociation reaction in the context of acid-base reactions. It is often given as its base-10 cologarithm, p K a. acid–base extraction A chemical reaction in which chemical species are separated from other acids and bases. acid ...

  7. Water-reactive substances - Wikipedia

    en.wikipedia.org/wiki/Water-reactive_substances

    Water-reactive substances [1] are those that spontaneously undergo a chemical reaction with water, often noted as generating flammable gas. [2] Some are highly reducing in nature. [ 3 ] Notable examples include alkali metals , lithium through caesium , and alkaline earth metals , magnesium through barium .

  8. Reaction mechanism - Wikipedia

    en.wikipedia.org/wiki/Reaction_mechanism

    In chemistry, a reaction mechanism is the step by step sequence of elementary reactions by which overall chemical reaction occurs. [1]A chemical mechanism is a theoretical conjecture that tries to describe in detail what takes place at each stage of an overall chemical reaction.

  9. Condensation reaction - Wikipedia

    en.wikipedia.org/wiki/Condensation_reaction

    In organic chemistry, a condensation reaction is a type of chemical reaction in which two molecules are combined to form a single molecule, usually with the loss of a small molecule such as water. [1] If water is lost, the reaction is also known as a dehydration synthesis.