moles 1 Flashcards
1
Q
what is RFM?
A
the mass of a formula unit of a substance
2
Q
how do you calculate RFM?
A
add all the RAMS of the atoms/ions
3
Q
what does percentage by mass show?
A
the mass of a substance that comes from a particular element
4
Q
how do you calculate percentage by mass?
A
mass of X / RFM x100
5
Q
what is a mole?
A
the unit of amount of a substance
6
Q
formula for moles (mass and RFM)
A
moles = mass/ RFM
7
Q
formula for mass?
A
mass = RFM X moles
8
Q
what is the empirical formula?
A
the simplest mole ratio of an element
9
Q
what is the molecular formula?
A
the actual number of atoms in a molecule
10
Q
what does limiting mean?
A
there is not enough of a substance
11
Q
what does excess mean?
A
there is more than enough
12
Q
what is the formula for % yield?
A
experimental/ theoretical x 100
