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Vocabulary
Moles to Moles
Mixed Problems
Mass to Mass
Miscellaneous
100
A conversion factor that relates the amounts in moles of any two substances involved in a chemical reaction.
What is mole ratio?
100
CO2 + 2LiOH --> Li2CO3 + H2O How many moles of lithium hydroxide are required to react with 20 mol of CO2?
What is 40 mol LiOH?
100
Mg + 2HCl --> MgCl2 + H2 How many grams of hydrogen will be produced if we start with 2 moles of hydrochloric acid and excess magnesium?
What is 2 g H2?
100
Mg + 2HCl --> MgCl2 + H2 What mass of hydrogen is produced from the reaction of 75 g HCl (MM=36.5 g/mol) and excess Mg?
What is 2.0 g H2?
100

6.022 x 10^23

What is Avagadro's number?

200

The relationship between relative quantities of reactants and products in a chemical reaction, typically a series of ratios.

What is stoichiometry?

200
6CO2 +6H2O --> C6H12O6 + 6O2 How many moles of carbon dioxide are needed to react with 3.25 mol of water in the reaction described above?
What is 3.25 mol CO2?
200
Mg + 2HCl --> MgCl2 + H2 What mass of hydrochloric acid (MM=36.5 g/mol) is needed to react with 2.50 moles of magnesium?
What is 182 g HCl?
200
2KClO3 --> 2KCl + 3O2 How many grams of KCl are produced if 5.0 g of KClO3 is decomposed?
What is 3 g KCl?
200

N2 + 3H2 --> 2NH3
In the reaction above, a student reacted 28 g of nitrogen gas with an excess of hydrogen gas. This would be used as the first step in the stoichiometry calculation.

What is the formula mass (molar mass) of nitrogen?

300
The reactant that determines the amounts of the other reactants that can combine--and the amount of product that can form--in a chemical reaction.
What is the limiting reactant?
300
2Mg +O2 --> 2MgO How many moles of magnesium oxide are produced from 1.2 moles of magnesium?
What is 1.2 mol MgO?
300
How many moles of aluminum atoms are needed to combine with 1.58 mol of oxygen molecules to make aluminum oxide?
What is 2.1 mol Al?
300
Sodium and chlorine react to produce sodium chloride (table salt; MM=58.5 g/mol). Determine the amount of product that can be produced from 24.7 g of sodium and excess chlorine.
What is 62 g NaCl?
300
How many moles are present in 34 grams of Cu(OH)2?
What is 0.35 mol Cu(OH)2?
400

The percent by mass of each element in a chemical compound.

What is percent composition?

400
Ammonia, NH3, is widely used as a fertilizer and in many household cleaners. How many moles of ammonia are produced when 6 mol of hydrogen gas react with an excess of nitrogen gas?
What is 4 mol NH3?
400
Ammonia decomposes to produce nitrogen and hydrogen gases. How many moles of H2 can be formed by the decomposition of 0.145 moles of ammonia?
What is 0.218 mol H2?
400
Sodium hydroxide reacts with sulfuric acid (H2SO4; MM=98.1 g/mol) to form water and sodium sulfate. How many grams of sodium sulfate (MM=124 g/mol) will be formed from 200 g NaOH (MM=40 g/mol) and an excess of sulfuric acid?
What is 355 g Na2SO4?
400
Write the complete balanced equation for the following reaction (include states): When lithium hydroxide pellets are added to a solution of sulfuric acid, lithium sulfate and water are formed.
What is: 2LiOH (s) + H2SO4 (aq) --> Li2SO4 (aq) + 2H2O (l)
500
States that mass is neither created nor destroyed during ordinary chemical or physical reactions. (This is why we balance chemical equations!)
What is the law of conservation of mass?
500
Hydrogen and oxygen gases react under a specific set of conditions to produce water. How many moles of oxygen would be required to produce 5.0 moles of water?
What is 2.5 mol O2?
500

Aluminum oxide reacts with iron to form Fe3O4 and Aluminum. Determine the limiting reactant when 5 moles of aluminum oxide reacts with 7 moles of iron.

What is iron?

500
When copper (II) chloride reacts with sodium nitrate, copper (II) nitrate and sodium chloride are formed. If 15 g CuCl2 (MM=134.5 g/mol) react with 20 g NaNO3 (MM=85 g/mol), how much sodium chloride (MM = 58.5 g/mol) can be formed?
What is 13.0 g NaCl?
500
This questions is worth 1000 points! SURPRISE! Chlorine gas reacts with potassium bromide to produce potassium chloride and bromine gas. How many grams of potassium chloride can be produced from 300. g each of chlorine and potassium bromide?
What is 188 g KCl?