Stoichiometry Review

What is a Excess Reagent?

• amount you end with

• what you run out of first

• what you have left over

• what you start with

Fe (s) + S (l) --> FeS (s)  

In the experiment above, 7.62 g of Fe are allowed to react with 8.67 g of S.
How much FeS is formed?

• 14.8 g

• 12.2 g

• 13.7 g

• 19.9 g

Tags

NGSS.HS-PS1-7

Using the diagram, determine the limiting reactant, the product formed is water.

• oxygen

• hydrogen

• none of the reactant are limiting

• both hydrogen and oxygen

Tags

NGSS.HS-PS1-7

P₄ + 6Cl₂ --> 4PCl₃ 
The reaction of 75.0g P₄ with excess chlorine gas produces 110g PCl₃ in lab. Find the theoretical yield and calculate percent yield for the reaction. 

• 78%

• 64%

• 27%

• 33%

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NGSS.HS-PS1-7

Theoretical yield = 73g
Actual yield = 62g
Calculate the percent yield.

• 16%

• 116%

• 85%

• 76%

Mole ratios are obtained from the

• balanced chemical equation

• periodic table

• molar mass

What is the mole ratio of H₂O to H₃PO₄ in the following chemical equation?   P₄O₁₀ + 6 H₂O --> 4 H₃PO₄ 

• 6:4

• 4:6

• 1:3

• 3:1

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NGSS.HS-PS1-7

2H₂   +   O₂  →  2H₂O
How many moles of water can be produced if 8 moles H₂ are used?

• 4 moles

• 8 moles

• 16 moles

• 2 moles

Tags

NGSS.HS-PS1-7

N₂ +  3H₂ → 2NH₃ 
How many moles of hydrogen are needed to react with 2 moles of nitrogen?

• 6

• 2

• 3

• 1

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NGSS.HS-PS1-7

Cl₂ + 2KBr → Br₂ + 2KCl
How many grams of potassium chloride (KCl) can be produced from 356 g of potassium bromide (KBr)?

• 749 g

• 223 g

• 479 g

• 814 g

Tags

NGSS.HS-PS1-7