Stoich
What is the mole ratio of H2O to H3PO4 in the following chemical equation? P4O10 + 6H2O -> 4H3PO4
3, 2
In the equation 2Al2O3 -> 4Al + 3O2, what is the mole ratio of aluminum to oxygen?
4:3
How many mole ratios can be correctly obtained from the chemical equation 2Al2O3(l) -> 4Al(s) + 3O2(g)
6
In the formation of silicon carbide represented by the chemical equation SiO2(s) + 3C(s)-> SiC(s) + 2CO(g), 8 mol of each reactant are available for the reaction. What substance is the excess reactant?
SiO2(s)
If the percentage yield for a chemical reaction is 80.0%, the
actual yield is 80.0 g for every theoretical yield of 100 g
To determine the limiting reactant in a chemical reaction involving known masses of the two reactants, which of the following would be most useful?
calculating the mass of a single product formed from each reactant
For a chemical reaction, percentage yield represents the
efficiency
Actual yield must be determined by
experiments
In most chemical reactions the amount of product obtained is
less than the theoretical yield
The actual yield of a chemical reaction is generally
less than the theoretical yield
The participation of reactants in a chemical reaction is restricted by the
limiting reactant
Which expression can be used to solve a mass-to-mole conversion for the equation 2HCl -> H2 + Cl2?
mass HCl x 1 mol HCl x 1 mol Cl2 molar mass HCl 2 mol HCl
The expression mass x 1 mol/molar mass has the unit
mol
A balanced chemical equation allows one to determine the
mole ratio of any two substances in the reaction
Which of the following factors does not affect the actual yield of a reaction
particles no longer reacting with each other
Which of the following mathematical expressions correctly states the relationship among percentage yield, actual yield, and theoretical yield?
percentage yield = actual yield/theoretical yield x 100 theoretical yield = actual yield/percentage yield x 100
The coefficients in a chemical equation represent the
relative numbers of moles of reactants and products
Fewer steps are required to solve stoichiometry problems when
the reactant is given in moles and the product is sought in moles
The limiting reactant of a reaction can be used to calculate the
theoretical yield