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  2. Limiting reagent - Wikipedia

    en.wikipedia.org/wiki/Limiting_reagent

    The limiting reagent must be identified in order to calculate the percentage yield of a reaction since the theoretical yield is defined as the amount of product obtained when the limiting reagent reacts completely.

  3. Symmetric mean absolute percentage error - Wikipedia

    en.wikipedia.org/wiki/Symmetric_mean_absolute...

    In contrast to the mean absolute percentage error, SMAPE has both a lower and an upper bound. Indeed, the formula above provides a result between 0% and 200%. Indeed, the formula above provides a result between 0% and 200%.

  4. Yield (chemistry) - Wikipedia

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

    In the section "Calculations of yields in the monitoring of reactions" in the 1996 4th edition of Vogel's Textbook of Practical Organic Chemistry (1978), the authors write that, "theoretical yield in an organic reaction is the weight of product which would be obtained if the reaction has proceeded to completion according to the chemical ...

  5. Conversion (chemistry) - Wikipedia

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

    Conversion and its related terms yield and selectivity are important terms in chemical reaction engineering.They are described as ratios of how much of a reactant has reacted (X — conversion, normally between zero and one), how much of a desired product was formed (Y — yield, normally also between zero and one) and how much desired product was formed in ratio to the undesired product(s) (S ...

  6. Mass fraction (chemistry) - Wikipedia

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

    Mass fraction can also be expressed, with a denominator of 100, as percentage by mass (in commercial contexts often called percentage by weight, abbreviated wt.% or % w/w; see mass versus weight). It is one way of expressing the composition of a mixture in a dimensionless size ; mole fraction (percentage by moles , mol%) and volume fraction ...

  7. Law of definite proportions - Wikipedia

    en.wikipedia.org/wiki/Law_of_definite_proportions

    The law of definite proportion was given by Joseph Proust in 1797. [2]I shall conclude by deducing from these experiments the principle I have established at the commencement of this memoir, viz. that iron like many other metals is subject to the law of nature which presides at every true combination, that is to say, that it unites with two constant proportions of oxygen.

  8. Defining equation (physical chemistry) - Wikipedia

    en.wikipedia.org/wiki/Defining_equation...

    Theoretical chemistry requires quantities from core physics, such as time, volume, temperature, and pressure.But the highly quantitative nature of physical chemistry, in a more specialized way than core physics, uses molar amounts of substance rather than simply counting numbers; this leads to the specialized definitions in this article.

  9. New York Regents Examinations - Wikipedia

    en.wikipedia.org/wiki/New_York_Regents_Examinations

    Most Regents exams consist of a single three-hour testing period. The exception is the Earth Science exam, which consists of a 41-minute (approximate) laboratory component, known as the Earth Science lab practical, given around two weeks prior to the three-hour exam. The Regents exams are administered in January, June, and August.