chp 6 ; mole concept and stoichiometry Flashcards
(9 cards)
1
Q
how to find out Mr
A
sum of Ar
2
Q
how to find the percentage mass of an element in a compound
A
Ar x no. of atoms / Mr of the compound x 100%
3
Q
how to find molecular formula from empirical formula
A
n = Mr / sum of Ar
4
Q
how to find mole
A
mass x molar mass
volume x 24 dm3
numberof particles x 6x10 23
5
Q
concentration of a solution
A
concentration (mol/dm3) = no of moles / volume of solvent
concentration (g/dm3) = mass of solute / volume of solvent
n = M x V
6
Q
A
7
Q
formula to find concentration of unknown solution
A
no. of moles of acid / no. of moles of alkali
8
Q
how to find percentage yield
A
actual yield / theorectical yield x 10l%
9
Q
how to find perfentage purity
A
mass of pure substance in sample / mass of samples x 100%
