Stoichiometry Flashcards
Define equivalence point in a titration.
Equivalence point in a titration pertains to the conditions when the two reagents (the titrant and analyte) are present in relative quantities that match the balanced chemical equation. At this point, neither of these reagents will remain in excess.
Define limiting reagent.
Limiting reagent in a chemical reaction is the reagent which will be completely consumed when the reaction proceeds to completion. As such, it is this reagent which defines how much product will form.
Define percent yield.
Percent yield is a ratio which compares how much product is formed or recovered versus how much would be formed theoretically if all of the limiting reagent is completely reacted.This can only be calculated if you have information about how much product is formed or recovered. It is calculated using the equation: mass of product recovered/ mass of product theoretically formed x 100%
Define percent composition in a mixture.
Percent composition in a mixture describes the ratio of how much chemical of interest is present in an overall mixture.Typical examples are how much iron is present in iron ore or how much aspirin is present in an aspirin tablet.Percent composition can be often be determined by finding the overall mass of the mixture and then subject the mixture to a chemical reaction specific to the chemical of interest. By finding how much product is formed or how much reagent is required, one can estimate how much original chemical was present. Percent composition is calculated using the equation: mass of chemical of interest/ mass of overall mixture x 100%.
Define mole ratio in a balanced equation.
The mole ratio indicates the proportions by which reagents react or products are formed.For example the following balanced equation:2H2 + O2 → 2H2O shows a mole ratio of 1 mol O2/ 2 mol H2O and 2 mol H2/ 2 mol H2O.
Define molar concentration.
Molar concentration is the amount of solute ( in moles) per liter of solution.
