4.4 MOLES 1 Flashcards
1
Q
how to calculate RFM:
A
add the relative atomic masses of the atoms or ions
2
Q
how to calculate percentage by mass?
A
% of x= (mass of x/ RFM) x 100
3
Q
moles equation:
A
moles= mass/ RFM
4
Q
what is the empirical formula?
A
- the empirical formula of a substance contains the simplest mole ratio of its elements
- it can be calculated from the masses or percentages of each element
1. convert the masses or percentages into moles
2. cancel down the mole ratio
3. write the simplest mole ratio into a formula
5
Q
example of the empirical formula:
A
C6H12 goes to CH2
6
Q
what is the molecular formula?
A
contains the actual number of atoms in a molecule, for example C6H12
7
Q
when is a substance limiting?
A
if there isn’t enough of a substance
8
Q
how to calculate % yield:
A
experimental/ theoretical x 100
