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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 HCl 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 and excess Mg?

What is 2.1 g H2?

100

N2 + 3H2 --> 2NH3 In the reaction above, a student reacted 28 g of nitrogen with an excess of hydrogen. According to the students measurements, the reaction produced 30.0 g of product. The theoretical yield was 34.0 g. What is the student's percent yield?

What is 88.2%?

200
The measured amount of product obtained after performing a chemical reaction.
What is actual yield?
200

6CO2 +6H2O --> C6H12O6 + 6O2 How many moles of C6H12O6 are needed to react with 3.25 mol of water in the reaction described above?

What is 0.542 mol C6H12O6?

200

Mg + 2HCl --> MgCl2 + H2 What mass of HCl is needed to react with 2.50 moles of magnesium?

What is 180. g HCl?

200

2KClO3 --> 2KCl + 3O2 How many grams of KCl are produced if 5.0 g of KClO3 is decomposed?

What is 3.0 g KCl?

200

What step in dimensional analysis allows one to change from one substance to another? 

Molar Ratio

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 because it will run out first.

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 are needed to combine with 1.58 mol of oxygen to make aluminum oxide?

What is 2.11 mol Al?

300

Sodium and chlorine react to produce sodium chloride. Determine the amount of product that can be produced from 24.7 g of sodium and excess chlorine.

What is 62.3 g NaCl?

300

What is the molar mass of potassium carbonate?

What is 138 g/mol K2CO3?

400
The ratio of the actual yield to the theoretical yield, multiplied by 100.
What is percent yield?
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 hydrogen can be formed by the decomposition of 0.145 moles of ammonia?

What is 0.218 mol H2?

400

Sodium hydroxide reacts with hydrogen sulfate to form water and sodium sulfate. How many grams of sodium sulfate will be formed from 200. g NaOH and an excess of hydrogen sulfate?

What is 355 g Na2SO4?

400

Write the complete balanced equation for the following reactants: 

Lithium hydroxide are added to a solution of hydrogen sulfate.

What is: 2LiOH + H2SO4  --> Li2SO4  + 2H2O

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 with limiting reactant when 5 moles of aluminum oxide reacts with 7 moles of iron. Show your work.

What is iron?

500

When copper (II) chloride reacts with sodium nitrate, copper (II) nitrate and sodium chloride are formed. If 15.0 g CuCl2 react with 20.0 g NaNO3, how many grams of sodium chloride  can be formed?

What is 13.0 g NaCl?

500

Chlorine gas reacts with potassium bromide.  How many grams of the potassium product can be produced from 300.0 g each of chlorine and potassium bromide?

What is 186.6 g KCl?