Limiting and Excess Reactants
Which reactant, limiting or excess, is used to calculate the amount of product?
What is the limiting reactant?
What unit should go on the top of the conversion factor?
The unit of the unknown (what you are trying to find).
The calculations done with the balanced equations to find the quatities of reactants or products.
What is Stoichiometry?
The correct coefficients for the reaction:
___Mg + ___Fe2O3 --> ___MgO + ____Fe
3 Mg + __1_Fe2O3 --> __3_MgO + __2__Fe
2 H2 + O2 --> 2 H2O
How many moles of O2 will be used if 9 moles of H2O are produced?
What is 4.5 moles of O2?
When is it necesarry to find the limiting reactant?
When there are two given amounts of reactants and none are in excess.
What conversion factor do you use when you convert moles to moles?
What is Mole Ratio.
The ratio of reactants/products found by coefficients in a balanced equation.
What is Ideal Mole Ratio.
The correct coefficients for the reaction:
___HgO --> ___Hg + ____O2
_2__HgO --> _2__Hg + ____O2
2 Fe2O3 --> 4 Fe + 3 O2
How many moles of Fe2O3 will form from 5.0 moles of Fe?
What is 2.5 moles Fe2O3
Fe3O4 + 4 CO--->3 Fe + 4 CO2
If you were given 6 moles of CO and 4 moles of Fe3O4, which would be your limiting reactant?
Limiting reactant is CO.
What conversion factor do you use when you convert moles to grams?
What is Molar Mass.
The mass of one mole of a substance as determined by its atomic mass from the periodic table.
What is Molar Mass?
The correct coefficients for the reaction:
___C2H4 + ___O2 --> ___CO2 + ____H2O
_1__C2H4 + _3__O2 --> __2_CO2 + __2__H2O
2 KClO3 --> 2 KCl + 3 O2
How many moles of KClO3 must decompose in order to produce 9 moles of oxygen gas?
What is 6 moles KClO3
2 Na + Cl2 --> 2 NaCl
If you were given 15 moles of Na and 7 moles of Cl2, which would be your excess reactant?
Na would be the excess reactant.
What would be the correct conversion factor if I were given grams of H2 and wanted to find moles of H2?
(1 mol H2)/(2.02 g H2)
The reactant the is completely used up during the reaction and used to calculate the amount of product.
What is Limiting Reactant.
The correct coefficients for the reaction:
___P + ___O2 --> ___P2O3
The correct coefficients for the reaction:
__4_P + _3__O2 --> __2_P2O3
2 Na + Cl2 --> 2 NaCl
How many grams of NaCl will be produced from 1.25 mol of chlorine gas reacting with sodium?
What is 146 g NaCl
2 H2 + O2 --> 2 H2O
If you were given 6 moles of O2 and 5.0 g of H2, which would be you limiting reactant?
H2 would be your limiting reactant
_____Fe+_____ O2---> ____Fe2O3
Find the mole ratio of Iron to Oxygen
What is 4:3
The correct coefficients for the reaction:
___ H3PO4 + ___ Ca(OH)2 --> ___ Ca3(PO4)2 + ____ H2O
2 H3PO4 + 3 Ca(OH)2 --> 1 Ca3(PO4)2 + 6 H2O
Fe3O4 + 4 CO--->3 Fe + 4 CO2 How many moles of CO are needed to react with 16.5 g of Fe3O4
What is .285 moles CO