Empirical/Molecular Formula
What's the difference between empirical and molecular formula?
Empirical formula is the simplified way of writing the element composition of a compound, while molecular formula is the actual/original way of writing the element composition of a compound.
What's the precent composition of each element in sodium bromide (NaBr)?
Na: 22.3%
Br: 77.7%
What's the first step in solving a limiting reactant equation?
Balancing the equation given.
What's a mole?
A unit of measurement represented by Avogadro's number (6.022x10^23), which measures large quantities of atoms, molecules, particles, ions, or electrons.
What does it mean for an equation to be balanced.
The number of atoms of an element is the same on both the reactants and products side.
How do you simplify the molecular formula to the empirical formula?
Divide by the number all subscripts in the formula are divisible by
What's the precent composition of each element in potassium cyanide (KCN)?
K: 59.9%
C: 18.4%
N: 21.6%
Equation: C3H8 + O2 -> CO2 + H2O
If you have 14.8g of C3H8 and 3.44g of O2, which one is the limiting reactant?
O2
What's the molar mass?
The sum of the total mass in grams of all atoms in one mole of a substance.
Balance the following equation:
_ P4 + _O2 -> _ P2O3
1P4 +3O2->2P2O3
What is the empirical formula of C2H6O2?
CH3O
What's the precent composition of each element in magnesium carbonate (MgCO3)?
Mg: 28.15%
C: 13.92%
O: 57.93%
Equation: C3H8 + O2 -> CO2 + H2O
C3H8: 14.8g
O2: 3.44g
What's the number of grams of CO2 and of H20 produced?
CO2: 2.84g
H2O: 1.55g
Whats the Excess?
The reactant that there is more than enough of it to react with the limiting reactant or the reactant that is not completely used up after the chemical reaction ends.
Balance the following equation:
_N2+_H2->_NH3
1N2 +3H2->2NH3
What is the molecular formula of X7Y2?
X49Y14
What's the precent composition of each element in nickel (III) sulfate (NiSO4)?
Ni: 37.93%
S: 20.72%
O: 41.35%
Equation: C3H8 + O2 -> CO2 + H2O
C3H8: 14.8g
O2: 3.44g
How much excess is left?
C3H8: 13.9g
What's the limiting reagent/reactant?
The reactant in a chemical reaction that is completely used up in the reaction, once it is totally consumed the reaction stops. (basically it determines how much product will result from the reaction)
Balance the following equation:
_BaS + _PtF2 -> _BaF2 + _PtS
1BaS+1PtF2->1BaF2 +1PtS
Whats the empirical formula of NaCl?
NaCl
What's the precent composition of each element in ammonium sulfite (NH4)2SO3?
N: 24.0%
H: 6.91%
S: 27.5%
O:41.12%
Equation: AgNO3 + FeCl3 -> AgCl + Fe(NO3)3
AgNO3: 25g
FeCl3: 45g
What's the maximum number of grams of AgCl that would be produced?
AgCl: 21.1g
Whats the Law of Definite Proportions?
A law that states that every chemical reaction contains the exact same proportions of elements by mass.
Balance the following equation:
_AlBr3 + _K2SO4 -> _KBr + _Al2(SO4)3
2 AlBr3 + 3 K2SO4->6 KBr + 1 Al2(SO4)3