Show:
General Stoichiometry
Mole to Mole Problems
Molar Mass and
Mass to Mass
Limiting Reagents
Percent Yield
100

What is stoichiometry?

the mathematical calculation of relative products and reactants in a balanced chemical equation

100

What is the term for the ratio between the coefficients of any two reactants or products in a balanced chemical equation?

mole ratio

100

Calculate Molar mass of HCl (round to 2 decimal points)

36.46 g/mol

100

What is another name for limiting reagents?

limiting reactants

100
What is percent yield?
a comparison, expressed as a percentage, of how much product is made compared to the maximum that theoretically could have been made
200

What do the coefficients in a balanced equation tell us?

the number of moles present for each substance

200

How can you tell when something is going to be a mole ratio problem?

When there is only one number given (in moles), and the other number the question is asking for is also in moles

200

Calculate Molar Mass of K2(SO4)

174.26 g/mol

200

After you have completed your two equations when doing a limiting reagent problem, how can you tell which is the limiting reagent?

the reactant that produces the smallest amount of product

200
What is the formula for percent yield?
actual yield/theoretical yield x 100
300

Stoichiometry must always start with a ________________ chemical equation.

balanced

300

If 3 moles Al2O3 decompose, how many moles of oxygen are produced? 2Al2O3 -> 4Al + 3O2

4.5 moles O2

300

Calculate Molar mass of ammonium carbonate

96.09 g/mol

300

What is a limiting reactant? (What does it do?)

A limiting reactant in a chemical reaction is the substance that -Is used up first -Stops the reaction -Limits the amount of product that can form

300
What are two ways that your percent yield could be less than 100%?
inaccurate balances, bad techniques, spills, etc.
400

What is the difference between molecules and formula units?

molecules is a term used for covalent compounds and formula units is a term used for ionic compounds

400

If 3.6 moles of C2H2 are burned, how many moles of CO2 are produced? 2C2H2 + 5O2 --> 4CO2 + 2H2O

7.2 moles CO2

400

6.50 grams of aluminum reacts with an excess of oxygen. How many grams of aluminum oxide are formed? 4Al + 3O2 --> 2Al2O3

12.3 g Al2O3

400

How can you tell if a problem is a limiting reagent problem (other than it specifically saying so)?

You will have two givens that are the amounts of two reactants in grams

400
What is one way that your percent yield could be over 100%? (This happened in many of your experiments).
if you must remove water from a product by heating to leave a pure solid and it is not completely dry, it will weigh more than expected
500

What are two things that are always conserved in a chemical reaction?

mass, matter (atoms)

500

Write the balanced chemical equation for the reaction between hydrochloric acid and calcium carbonate when the products of the reaction are calcium chloride, carbon dioxide, and water.

2HCl + CaCO3 ---> CaCl2 + CO2 + H2O

500

If 10.1 g of Fe are added to a solution of Copper (II) Sulfate, how many grams of solid copper would form? 2Fe + 3CuSO4 --> Fe2(SO4)3 + 3Cu

17.2g Cu

500

50g of Al are added to 100g HCl, how many grams of H2 are produced? 2Al + 6HCl --> 2AlCl3 + 3H2

2.74g H2

500
21g of CaCO3 produce 7.2g of CaO, what is the % yield? CaCO3 --> CaO + CO2
61.2%