Empirical Formulas
The empirical formula for methane
(hint: the same as the molecular formula)
CH4
The molecular formula for tetranitrogen pentoxide
N4O5
The charge on a ferrous ion
+2
ferric ion is +3
An easily separable and/or differentiable solution of 2 or more substances
Heterogenous Solution
The formula for percent yield
(actual/theoretical) x 100
The empirical formula for the following compound:
C7H14O21
CH2O3
Formula for magnesium chloride
MgCl2
The charge on a cupric ion
+2
Cuprous would be +1
An example of this type of property is reactivity
chemical property
Percent yield given the actual yield was 63.4 grams and the theoretical yield was 79.8 grams
79.5% yield
(63.4/79.8)*100%
The empirical formula of the following compound:
C56H72O32
C7H9O4
Formula for lead (IV) sulfide
PbS2
Charge on the sulfate ion
-2
A property of matter that is dependent of amount
extensive property
e.g. volume, mass, density
Actual yield given a percent yield of 64% and a theoretical yield of 214.8 grams
137.5 grams
(214.8)*(64/100)
The molecular formula for a hydrocarbon given the formula weight is 129.12 amu and the empirical formula is C2H3O
C6H9O3
6 x C = 12.01 x 6 = 72.06
9 x H = 1.01 x 9 = 9.07
3 x O = 16.00 x 3 = 48.00
72.06+9.07+48
Formula for cuprous nitride
Cu3N
+1
a property of matter that is independent of amount
intensive
e.g. color, smell...
Theoretical yield given the actual yield was 12 grams and the percent yield was 41%
29.3 grams
(12/theoretical yield) = 0.41
The empirical formula of glucose
Empirical: CH2O
The formula for ammonium bicarbonate
NH4HCO3
OR
CH5NO3
(top is more correct, chemical formula)
Dichromate ion formula and charge
Cr2O7 (2-)
The atmosphere is an example of this kind of mixture
homogeneous mixture
2H2 (g) + O2 (g) -> 2H2O (l)
The percent yield given I reacted 17 grams of hydrogen gas with excess oxygen and I actually produced 135 grams of H2O
89%
Theoretical yield:
(17 grams H2) * (1 mol H2/2.02 grams H2) * (2 mol H2O/2 mol H2) * (18.02 grams H2O/1 mol H2O) = 151.65 grams
135 grams (actual) / 151.65 grams (theoretical) = 0.89 = 89% yield