Mix
Moles
Stoich
Limiting Reagent
% Yield
100
This is the branch of chemistry that deals with mass relationships in compounds and reactions.
What is Stoichiometry
100
Balance the following reaction:
H2 + O2 → H2O
What is
2H2 + O2 → 2H2O
100
This is the amount of magnesium chloride produced (in grams) if 0.80 moles of magnesium react with excess hydrochloric acid (unbalanced)
Mg + HCl → MgCl2 + H2
What is 76.2 grams
100
This is the ingredient that is the limiting reactant if you have 5 cups of flour, 9 eggs and 3 tbs of oil? Given:
2 cups flour + 3 eggs + 1 tbs oil → 4 waffles
What is flour?
100
The percent yield tells you a ratio between the actual yield and the _________ yield of a certain product.
What is theoretical
200
In a chemical reaction, these numbers can be used to determine the mole ratio of any reactants and/or products.
What are coefficients?
200
What is the correctly balanced form of the equation:
(NH4)NO2 → N2 + H2O
What is
(NH4)NO2 → N2 + 2H2O
200
This is the amount of lithium nitride (molar mass = 3*6.941 + 14.01 = 34.833 grams/mol) produced if 1 mole of Lithium reacts with an excess of nitrogen gas. The reaction:
6 Li + N2 → 2 Li3N
What is 11.6 grams Li3N (34.833/3 = 11.61 g)
200
In a chemical reaction, reactants that are not used up when the reaction is finished are called...
What is excess reactants?
200
This is the actual amount of grams produced if the theoretical yield of a reaction is 42.0 grams of product and the percent yield is 75%.
What is 31.5 g (0.75*42.0)
300
These are the units of molar mass.
What is g/mol.
300
This is the number of moles of water that are made from a complete reaction of 2.2 moles of oxygen gas with hydrogen gas, given the reaction:
2H2 + O2 → 2H2O
What is 4.4 moles?
300
This is the amount of calcium carbonate produced when a chemistry student reacts 2 moles of CaO with an excess of CO2. (It's balanced.)
CO2 + CaO --> CaCO3
What is 200.2 grams CaCO3 (molar mass = 100.1 g/mol)
300
There are 100.0 grams of each reactant available. Determine the limiting reactant in this equation.
SO2 + 2NaOH → Na2SO3 + H2O
What is NaOH?
100. g SO2 = 1.56 mol which makes 1.56 mol of Na2SO3
100.g of NaOH makes 1.25 mole of Na2SO3
300
This is the percent yield when a sample of 8.5 g NH3 in oxidation produces 4.5 g of NO (molar mass = 14 + 16). Reaction:
4 NH3 + 5 O2 → 4 NO + 6 H2O
What is 30. % (4.5 / 15)
8.5 g of NH3 is 50% of the molar mass (17.0 g).
MM of NO is 30.0 g -> expect 15.0 g
400
In the reaction represented by the equation
2Al2O3 → 4Al + 3O2, this is the mole ratio of Aluminum to Aluminum Oxide.
What is 2:1 (4:2 ok)
400
This is the amount of moles of H2 that can be made from the complete reaction of 3.0 moles of Al, given:
2 Al + 6 HCl → 2 AlCl3 + 3 H2
What is 4.5 moles of H2
400
This is the amount (in grams) of zinc chloride (molar mass = 136.1 g) produced from the reaction of 202.7 grams of lithium chloride (molar mass = 42.39 g) and an excess of zinc.
(Assume that Zn has a charge of +2.)
(You write & balance the equation first.)
Zn + 2LiCl → ZnCl2 + 2Li
What is 325.9 g
x 
x 
x 
= 325.9 g ZnCl2
400
This is the theoretical yield of silicon carbide (SiC) if 50.0 grams of silicon dioxide reacts with 79.1 grams of Carbon. (Balance it first.)
SiO2 + C → SiC + CO
What is 33.4 g (Limiting reagent is SiO2)
C - enough to produce 264.3 g of SiC, but not nearly enough SiO2.
x 
x 
x 
= 33.4 g SiC
400
This is the limiting reagant if 155 grams of calcium carbonate (molar mass = 40.1 + 12.0 + 48.0 = 100.1) is reacted with 150 grams of hydrochloric acid (molar mass = 35.45 + 1.01 = 36.46) and 142 grams of calcium chloride (molar mass = 40.1 + 70.9= 111.0) is obtained?
+150 if percent yield is within 5%
CaCO3 + 2HCl → CaCl2 + CO2 + H2O
What is CaCO3?
What is 82.6% (77.6% - 87.6 %)
500
This is the molar mass of Copper(II) Sulfate.
What is a 159.6 g/mol OK: 160 g/mol?
CuSO4
Cu 63.55
S 32.07
O (4) 64.00
___________
159.6
500
This is how many moles of LiOH are required to react with 20 moles of CO2 in the following reaction:
CO2 + 2LiOH → Li2CO3 + H2O
What is 40 moles.
500
This is the amount (in grams) of aluminum oxide (molar mass = 102.0 g)produced from the reaction of 0.353 grams solid aluminum (molar mass = 27.0 g) with an excess of oxygen gas.
You write the equation and balance it first.
What is 0.667 grams.
4Al + 3O2 → 2Al2O3
x 
x 
x 
= 0.667 g Al2O3
500
This is the amount (g) of lead chloride (PbCl2) formed if 135.8g of sodium chloride reacts with 95.7g of lead(II) in a single replacement reaction.
You write and balance the equation first.
Pb + 2NaCl --> 2Na + PbCl2
What is 128.5 g PbCl2
(Pb is the limiting reagent)
x 
x 
x 
= 128.5 g PbCl2
500
This is the limiting reagent and percent yield of CuS given that you start with 15.5 g Na2S (molar mass = 46.0 + 32.1 = 78.1) and 12.1 g CuSO4 (molar mass = 46.0 + 32.1 + 64.0 = 159.7). The actual amount of CuS produced was 3.05g . Reaction:
Na2S + CuSO4 → Na2SO4 + CuS
What is CuSO4?
What is 42.1%? (0.0319/0.0758 = 0.4208 ~ 42.1%) +/- 5% -> 37.1% to 47.1%