Vocab
A chemical formula that shows the number of atoms in each element in a molecule of a compound.
Molecular Formula
Whats the mole ratio of HCl to H2?
_Mg + _HCl > _MgCl2 + _H2
2:1
If given 8.35 grams of H2, how many grams of H2O are produced?
2H2 + O2 →2H2O
74.49 grams of H2O
(Actual yield/theoretical yield) x 100%
What is the empirical formula of the compound that has C6H10O4 as the molecular formula?
C3H5O2
The amount of product expected to form from a given amount of reactant if the reaction goes to completion.
Theoretical Yield.
How many moles of H2O are produced if 2.00 moles of O2 are used?
4NH3 + 5O2 = 6H2O + 4NO
2.40 mol H2O
If given 68 grams of H2, How many grams of O2 are produced?
2H2 + O2 →2H2O
538.61 grams O2
The actual yield from an experiment is 48.8g of H2O. You calculate that the theoretical yield is 55.0g H2O. What is the percent yield?
88.7%
What is the molecular formula of a compound with an empirical formula of HCO2 and a molar mass of 90g/mol
H2C2O4
How much product you actually got from a reaction.
Percent Yield
Given the following equation, how many moles of Nitrogen are needed to get 12 moles of NH3?
N2 + 3H2 =2NH3
2 mol N2
How many grams of C3H6 reacted, if 22.3 grams of CO are produced?
C3H6 + 3O2 → 3CO + 3H2O
11.2g of C3H6
Given that the actual yield of Nitric acid is 3.07 grams and that the theoretical yield was 10 grams, calculate the percent yield.
30.7%
What is the molecular formula of a substance that is 14.3% Hydrogen, 85.7% Carbon and has a molecular mass of 56.0 g/mol?
C4H8
The relationship between the relative quantities of substances taking part in a reaction or forming a compound, typically a ratio of whole integers
Stoichiometry
How many moles of potassium nitrate are produced when 2.5 moles of potassium phosphate react?
K3PO4 + Al(NO3)3 → 3KNO3 + AlPO4
7.5 mol of potassium nitrate
How many grams of oxygen can be produced from 15.2 grams of gallium oxide?
2Ga2O3 → 4Ga + 3O2
3.89g O2
A chemical reaction was supposed to produce 3.48g of barium sulfate but only produced 2.96g. What's the percent yield and percent error?
% Yield: 85.06%
% error: 14.94%
The empirical formula of a compound of boron and hydrogen is BH3. Its molar mass is 27.7g/mol. Determine the molecular formula of the compound.
B2H6
The percentage by mass of each element in a compound.
Percent composition
How many moles of oxygen are produced by the decomposition of 6.0 moles of potassium chlorate?
2KClO3 → 2KCl + 3O2
9 mol of Oxygen
25g of potassium chlorate will produce how many grams of oxygen? BALANCE THE EQUATION FIRST!
KClO3 = KCl + O2
50.3g KCl
Using the balanced equation below. If 40 grams of acetylene (C2H2) and 65 grams of oxygen are used, and 12 grams of water are produced, what is the percent yield?
2C2H2 + 5O2 > 4CO2 + 2H2O
88.86%
A compound is composed of 52.14% carbon, 13.13% hydrogen and 34.73% oxygen by mass. What is the empirical formula?
If the molar mass is 138.204 g/mol, what is the molecular formula?
Empirical formula: C2H6O, Molecular formula: C6H18O3