Calculations - equations Flashcards
1
Q
Relative formula mass
A
Add up the relative atomic masses of the elements in the molecule
2
Q
Percentage mass of an element in a compound
A
(Relative atomic mass x no. of atoms of that element) ÷ Mr
Answer x 100
3
Q
Moles
A
Number of moles = mass in g ÷ Mr
n = m ÷ Mr
4
Q
Volume of gas
A
Volume of gas = moles x 24
v = n x 24
5
Q
Concentration
A
Concentration = mass of solvent ÷ volume of solvent
c = m ÷ v
6
Q
Molar concentration
A
Concentration = moles of solvent ÷ volume of solvent in dm
c = n ÷ v
7
Q
Titration calculation
A
Calculate moles, use the ratio in the equation then find the unknown concentration
(n = c x v)
8
Q
Atom economy
A
Mr of desired product ÷ mr of all products
Answer x 100
9
Q
Percentage yield
A
Actual mass of product ÷ maximum theoretical mass of product
Answer x 100
