Unit 12 Mole Calculation Flashcards
Converting between moles and number of particles
Number of particles = Avogadro constant x no. of moles of the substance
Molar mass (Definition)
The mass of one mole of a substance
Unit: g mol-1
Number of moles of substance (mol)
Mass of substance (g) / molar mass of substance (g mole-1)
Percentage of mass of an element in a compound
(Number of atoms of the element in formula x relative atomic mass of the element) / formula mass or relative molecular mass of the compound x100%
Water of crystallisation (DEFINITION)
The water that is necessary for the formation of crystal
Hydrated (DEFINITION)
Compounds that contain water of crystallisation
Anhydrous (DEFINITION)
compounds that have lost their water of crystallisation
Empirical formula (DEFINITION)
empirical formula of a compound gives the simplest whole number ratio of two time of ions in the compound
Experimental procedures (from the experimental data)
Weigh the metal on an electronic balance.
Weigh the crucible, lid separately.
Heat the metal until there is no further change.
Allow it to cool.
Find the mass of the crucible lid and the product formed.
Repeat heating until a constant mass is obtained.
Stoichoimetric scale
About the number, but not mass
UNIT CONVERSION
1000g = 1kg
1000 000 g = 1 tonnes
Limiting Reactant (DEFINITION)
the amount of reactant will be used up in the reaction
