Stoichiometry and Percent Yield

Molar Mass

100

What is the Molar Mass of Zirconium?(include units)

91.22g/mol

200

What is the Molar Mass of Sodium Chloride(NaCl)?

58.45g/mol

300

What is the Molar Mass of CaCO₃? (include units)

100.09g/mol

400

What is the Molar Mass of Mg(OH)₂? (include units)

58.33g/mol

500

What is the Molar Mass of Ammonium Thiocyanate? (include units)

76.14g/mol

Balancing Chemical Equations

100

_Cu(OH)₂ -> _H₂O + _CuO

1Cu(OH)₂ -> 1H₂O + 1CuO

200

_N₂ + _O₂ -> _N₂O

1N₂ + 1O₂ -> 2N₂O

300

_Pb + _H₃PO₄ -> _H₂ + _Pb₃(PO₄)₂

3Pb + 2H₃PO₄ -> 3H₂ + 1Pb₃(PO₄)₂

400

_HCl + _K₂CO₃ -> _CO₂ + _H₂O + _KCl

2HCl + 1K₂CO₃ -> 1CO₂ + 1H₂O + 2KCl

500

_Li₃N + _NH₄NO₃ -> _LiNO₃ + _(NH₄)₃N

1Li₃N + 3NH₄NO₃ -> 3LiNO₃ + 1(NH₄)₃N

Stoichiometry

100

How many moles are in 37.5g of hydrochloric acid (HCl)?

0.64 moles HCl

200

Mg + 2HCl -> MgCl₂ + H₂

How many moles of H₂ are produced when 17.3g of Magnesium are reacted with hydrochloric acid(HCl)?

1.42 moles H₂

300

2NH₃ + H₂SO₄ -> (NH₄)₂SO₄

How many grams of of ammonia (NH₃) are needed to make 30.6g of ammonium sulfate ((NH₄)₂SO₄)?

7.74g ammonia

400

2C₆H₁₄ + 19O₂ -> 12CO₂ + 14H₂O

How many molecules of O₂ are needed to completely combust 23.0g of hexane(C₆H₁₄)?

1.53x10²⁴ molecules of O₂ 

500

4P + 5O₂ -> P₄O₁₀

How many atoms of phosphorus(P) are needed to produce 7.03x10²³molecules of P₄O₁₀? 

2.812x10²⁴ atoms of phosphorus

Types of Reactions

100

What type of reaction is this?

2S + 3O₂ -> 2SO₃

Synthesis

200

What type of reaction is this?

2H₂O -> 2H₂ + O₂

Decomposition

300

What type of reaction is this? 

2C₈H₁₈ + 25O₂ -> 16CO₂ + 18H₂O

Combustion

400

What kind of reaction is this?

Li₃N + NH₄NO₃ -> LiNO₃ + (NH₄)₃N

Double Replacement

500

What type of reaction is this?

2H₃PO₄ + 3Ba(OH)₂ -> 6H₂O + Ba₃(PO₄)₂

Acid-Base Neutralization

Mole Ratios andPercent Yield

100

2NaBr + Ca(OH)₂ -> CaBr₂ + 2NaOH

What is the coefficient on sodium bromide?

2

200

2Al₂O₃ -> 2Al + 3O₂

What is the mole ratio of O₂ to Al₂O₃?

3O₂/2Al₂O₃ or 3O₂:2Al₂O₃

300

After a combustion reaction, you expected to get 20g of water. You measured 15.7g. What is the percent yield? 

78.5%

400

2Al + 6HCl -> 3H₂ + 2AlCl₃

What is the theoretical yield of AlCl₃ if you start with 2.3moles of Aluminum?

306.66g AlCl₃

500

CaCO₃ -> CaO + CO₂ 

You are decomposing 10g of Calcium Carbonate(CaCO₃). You received 4.8g of Calcium Oxide(CaO) from the reaction. What is your percent yield? (hint: find the theoretical yield first)

Molar Masses: CaCO₃=100.09g/mol, CaO=56.08g/mol

85.7% yield