Chapter 5 - Chemical Calculations Flashcards
what is molar mass?
the mass, in grams, of 1 mole of a substance
what does it mean by Avogadro constant?
the number (6 x 10 *23) of characterisitic particles in 1 mole of a substance
what does it mean by limited reactant?
the reactant that is not in excess
what does it mean by percentage yield?
a measure of the actual yield of a reaction when carried out experimentally compared to the theoretical yield calculated from the equation:
actual yield x 100
predicted yield
what does it mean by percentage purity?
a measure of the purity of the product from a reaction carried out experimentally
percentage purity =
mass of pure product x100
mass of impure product
what does it mean by percentage composition?
the percentage by the mass of each element in a compound
what is Avogadro’s law?
equal volumes of any gas, under the same conditions of temperature and pressure, contain the same number of particles
what does the acronym r.t.p stand for?
room temperature and pressure; the standard values are 25C/298K and 101.3kPa/1 atmosphere pressure
what is molar gas volume?
1 mole of any gas has the same volume under the same conditions of temperature and pressure (24dm cubed at r.t.p)
what is mass concentration?
the measure of the concentration of a solution in terms of the mass of the solute, in grams, dissolved per cubic decimetre of solution (g/dm cubed)
what is molar concentration?
the measure of the concentration of a solution in terms of the number of moles of the solute dissolved per cubic decimetre of solution (g/dm cubed)
what is a standard solution?
a solution whose concentration is know precisely - this solution is then used to find the concentration of another solution by titration
what is titration?
a method of quantitative analysis using solutions: one solution is slowly added to a known volume of another solution using a burette until an end-point is reached
