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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. RCA clean - Wikipedia

    en.wikipedia.org/wiki/RCA_clean

    The first step (called SC-1, where SC stands for Standard Clean) is performed with a solution of (ratios may vary) [2] 5 parts of deionized water; 1 part of ammonia water, (29% by weight of NH 3) 1 part of aqueous H 2 O 2 (hydrogen peroxide, 30%) at 75 or 80 °C [1] typically for 10 minutes. This base-peroxide mixture removes organic residues.

  4. Standard state - Wikipedia

    en.wikipedia.org/wiki/Standard_state

    The standard state of a material (pure substance, mixture or solution) is a reference point used to calculate its properties under different conditions.A degree sign (°) or a superscript Plimsoll symbol (⦵) is used to designate a thermodynamic quantity in the standard state, such as change in enthalpy (ΔH°), change in entropy (ΔS°), or change in Gibbs free energy (ΔG°).

  5. Solution (chemistry) - Wikipedia

    en.wikipedia.org/wiki/Solution_(chemistry)

    Making a saline water solution by dissolving table salt in water.The salt is the solute and the water the solvent. In chemistry, a solution is defined by IUPAC as "A liquid or solid phase containing more than one substance, when for convenience one (or more) substance, which is called the solvent, is treated differently from the other substances, which are called solutes.

  6. Internal standard - Wikipedia

    en.wikipedia.org/wiki/Internal_standard

    In NMR spectroscopy, e.g. of the nuclei 1 H, 13 C and 29 Si, frequencies depend on the magnetic field, which is not the same across all experiments. Therefore, frequencies are reported as relative differences to tetramethylsilane (TMS), an internal standard that George Tiers proposed in 1958 and that the International Union of Pure and Applied Chemistry has since endorsed.

  7. Matrix (chemical analysis) - Wikipedia

    en.wikipedia.org/wiki/Matrix_(chemical_analysis)

    A(standard) is the peak area of analyte in the absence of matrix. The concentration of analyte in both standards should be the same. A matrix effect value close to 100 indicates absence of matrix influence. A matrix effect value of less than 100 indicates suppression, while a value larger than 100 is a sign of matrix enhancement.

  8. Standard addition - Wikipedia

    en.wikipedia.org/wiki/Standard_addition

    The Standard addition method, often used in analytical chemistry, quantifies the analyte present in an unknown. This method is useful for analyzing complex samples where a matrix effect interferes with the analyte signal.

  9. Standard hydrogen electrode - Wikipedia

    en.wikipedia.org/wiki/Standard_hydrogen_electrode

    During the early development of electrochemistry, researchers used the normal hydrogen electrode as their standard for zero potential. This was convenient because it could actually be constructed by "[immersing] a platinum electrode into a solution of 1 N strong acid and [bubbling] hydrogen gas through the solution at about 1 atm pressure".