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  2. Standard solution - Wikipedia

    en.wikipedia.org/wiki/Standard_solution

    In analytical chemistry, a standard solution (titrant or titrator) is a solution containing an accurately known concentration. Standard solutions are generally prepared by dissolving a solute of known mass into a solvent to a precise volume, or by diluting a solution of known concentration with more solvent. [ 1 ]

  3. Hydrogen chloride - Wikipedia

    en.wikipedia.org/wiki/Hydrogen_chloride

    Flame inside HCl oven. Hydrogen chloride is produced by combining chlorine and hydrogen: Cl 2 + H 2 → 2 HCl. As the reaction is exothermic, the installation is called an HCl oven or HCl burner. The resulting hydrogen chloride gas is absorbed in deionized water, resulting in chemically pure hydrochloric acid. This reaction can give a very pure ...

  4. Hydrogen bond - Wikipedia

    en.wikipedia.org/wiki/Hydrogen_bond

    A single hydrogen atom can participate in two hydrogen bonds. This type of bonding is called "bifurcated" (split in two or "two-forked"). It can exist, for instance, in complex organic molecules. [46] It has been suggested that a bifurcated hydrogen atom is an essential step in water reorientation. [47]

  5. Nitrosyl chloride - Wikipedia

    en.wikipedia.org/wiki/Nitrosyl_chloride

    A more convenient laboratory method involves the (reversible) dehydration of nitrous acid by HCl [4] HNO 2 + HCl → H 2 O + NOCl. By the direct combination of chlorine and nitric oxide; This reaction reverses above 100 °C. Cl 2 + 2 NO → 2 NOCl. By reduction of nitrogen dioxide with hydrogen chloride: [5] 2NO 2 + 4 HCl → 2NOCl + 2H 2 O + Cl 2

  6. Qualitative inorganic analysis - Wikipedia

    en.wikipedia.org/wiki/Qualitative_inorganic_analysis

    The reagent used can be any substance that gives S 2− ions in such solutions; most commonly used are hydrogen sulfide (at 0.2-0.3 M), thioacetamide (at 0.3-0.6 M), addition of hydrogen sulfide can often prove to be a lumbersome process and therefore sodium sulfide can also serve the purpose. The test with the sulfide ion must be conducted in ...

  7. Hydrogen-bonded organic framework - Wikipedia

    en.wikipedia.org/wiki/Hydrogen-bonded_organic...

    Hydrogen bonds formed among various monomers guarantee the construction of hydrogen-bonded organic frameworks with different assembly architectures. [15] [16] [17] The constitution of the hydrogen pairs is based on the structural and functional design of the HOFs, therefore different hydrogen bonding pairs should be selected following systematic requirements.

  8. Hydrogen-bond catalysis - Wikipedia

    en.wikipedia.org/wiki/Hydrogen-bond_catalysis

    Hydrogen-bond catalysis is a type of organocatalysis that relies on use of hydrogen bonding interactions to accelerate and control organic reactions. In biological systems, hydrogen bonding plays a key role in many enzymatic reactions, both in orienting the substrate molecules and lowering barriers to reaction. [ 1 ]

  9. Hydrohalogenation - Wikipedia

    en.wikipedia.org/wiki/Hydrohalogenation

    A hydrohalogenation reaction is the electrophilic addition of hydrogen halides like hydrogen chloride or hydrogen bromide to alkenes to yield the corresponding haloalkanes. [ 1 ] [ 2 ] [ 3 ] If the two carbon atoms at the double bond are linked to a different number of hydrogen atoms, the halogen is found preferentially at the carbon with fewer ...