Given the mass of the reactants, using mole ratio determine the mass of the products.
Divide Mass by Molar Mass of reactant.
Use Mole Ratio to convert the moles of reactant to moles of product
Multiple Moles of Products to Molar Mass of Product
Receive final answer for Theoretical Yield for mass of Product.
1.4.2 Determine the limiting reactant and the reactant in excess when quantities of reacting substances are given.
If one mole of substances reacts with one mole of substances, unless you have exact mass of each substances there will always be a limiting reactant and reactant in excess.
For example, if there are more hydrogen than oxygen required in one chemical reaction, then oxygen is the limiting reactant while hydrogen is in excess. Hence, "limiting" the reaction and "excess" which is more than enough.
Divide both reactant's mass by their respective molar mass to receive the moles.
The reactant with less moles is the limiting reagent.
The reactant with more moles is the reactant in excess.
1.4.3 Solve problems involving theoretical, experimental and percentage yield
Chemical reactions aren't completely efficient. Therefore the experimental yield (actual yield), is generally less than the theoretical yield predicted.
Percentage yield = Experimental yield / Theoretical yield x 100%
Change the equation around to receive different forms of the same equation.
1.4.4 Apply Avogadro's law to calculate reacting volumes of gases.
Avogadro's law states that equal volume of different gases contain equal numbers of particles at the same temperature and pressure.
1.4.5 Apply the concept of molar volume at standard temperature and pressure in calculations.
All gases have the same molar volume at the same temperature and pressure. The standard conditions of temperature and pressure (STP) are 273 K (0 degree Celcius) and 100 kPa pressure.
One mole of gas occupies 22.4 dm^3 under STP while it occupies 24.0 dm^3 under RTP (room temperature which is 298 K)
Number of moles = Volume / Molar Volume (22.4 dm^3 at STP and 24.0 dm^3 at RTP)
1.4.6 Solve problems involving the relationship between temperature, pressure and volume for a fixed mass of an ideal gas.
There are three laws of Gas.
Boyle's Law state that pressure of a gas is inversely proportional to the volume.
Gay-Lussac's Law state that pressure of a gas is directly proportional to the temperature
Charles's Law state that the volume is directly proportional to the temperature.
The Combined Gas Law simply combines them all to one equation.
Note: Temperature is measured in Kelvins.
How to use the Combined Gas Law, simply input the numbers into the equation. If the question states that one of them is constant, then you can remove it to use one of the three simple laws instead.
1.4.7 Solve problems using the ideal gas equation, PV = nRT
This is the Combined Gas Law
The Ideal Gas Equation adds the Avogadro's Law to the Combined Gas Law
P = Pressure
V = Volume
n = number of moles
T = Temperature in Kelvins
R = Gas Constant
The Gas Constant is 8.31 J K^-1 mol^-1.
The SI unit is Joules / (Kelvin x Moles)
1.4.8 Analysis graphs relating to the ideal gas equation.
Boyle's Law Graph
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