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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

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 g of product. The theoretical yield was 34 g. What is the student's percent yield?

What is 88%?

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 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

Avogadro's number.

What is 6.022 x 1023?

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

4Al + 3O2 --> 2Al2O3

What is 2.11 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.

2Na + Cl2 --> 2NaCl

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 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?

3H2 + N2 --> 2NH3

What is 4 mol NH3?

400

Ammonia (NH3) decomposes to produce nitrogen and hydrogen gases. How many moles of H2 can be formed by the decomposition of 0.145 moles of ammonia?

2NH3 --> N2 + 3H2

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?

2NaOH + H2SO4 --> 2H2O + Na2SO4

What is 355 g Na2SO4?

400

Write the complete balanced equation for the following reaction (including states): When solid lithium hydroxide pellets are added to an aqueous solution of sulfuric acid, aqueous 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?

2H2 + O2 --> 2H2O

What is 2.5 mol O2?

500

Aluminum oxide reacts with iron to form Fe2O3 and Aluminum. Determine with limiting reactant when 5 moles of aluminum oxide reacts with 7 moles of iron.

Al2O3 +2Fe --> Fe2O3 + 2Al

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?

CuCl2 + 2NaNO3 --> Cu(NO3)2 + 2NaCl

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?