Transcript Totaling Atoms Using PSEC - Mr. Jones's Science Class

Totaling Atoms Using PSEC
Parentheses
Count up the total number of atoms inside the parentheses
Subscripts
Multiply the total number of atoms inside the parentheses by the
subscript value
Extras
Add any extra atoms that were not yet accounted for to the total
Coefficients
Multiply the total number of atoms (from PSE) by the coefficient
Examples
2Ba(NO3)2
P – 4 atoms total
N 1
O 3
4 atoms
4(NH4)3PO4
Parentheses
P – 5 atoms total
N 1
H 4
5 atoms
S – 8 atoms total
Subscripts
E – 9 atoms total
Extras
E – 20 atoms total
C – 18 atoms total
Coefficients
C – 80 atoms total
(4)(2) = 8 atoms
8 + 1 = 9 atoms
(9)(2) = 18 atoms
S – 15 atoms total
(5)(3) = 15 atoms
15 + 5 = 20 atoms
(20)(4) = 80 atoms