Last Review for Stoichiometry

Carbon and Oxygen combine to form CO₂. If 10g of Carbon combines with Oxygen to produce 20g of CO₂ and 10g of Oxygen combines with Carbon to produce 15g of CO₂, How many grams of CO₂ are produced from 10g of Carbon and 10g of Oxygen?

• 20g of CO₂
• 15g of CO₂
• 17.5g of CO₂
• 25g of CO₂

The Formula to make S'mores is:
2C + 1M + G₂ → C₂MG₂. If you have 5 Marshmallows (M), 9 Chocolate Pieces (C), and 9 Graham Cracker Halves (G), how many S'mores can you make?

• 5
• 4
• 8
• 42

Fe + S --> FeS
If 7.62g Fe react with 8.67g S, what is the limiting reactant?

• Fe
• S
• FeS
• none 

Tags

NGSS.HS-PS1-7

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

• 1.16%
• 116%
• 85%
• 76%

4NH₃ + 5O₂ --> 4NO + 6H₂O
How many grams of NO are formed if 6.30g of ammonia react with 1.80g of oxygen? 

• 0.37g
• 0.045g
• 1.35g
• 11.1g

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%

Tags

NGSS.HS-PS1-7

4NH₃ + 5O₂ --> 4NO + 6H₂O
How many grams of NO are formed if 6.30g of ammonia react with 1.80g of oxygen? 

• 0.37g
• 0.045g
• 1.35g
• 11.1g

How many molecules are in 2.5 mol of NaCl?

• 1.50 x10²⁴ molecules

• 1.50 molecules

• 4.15 molecules

• 1.51 x10²⁴ molecules

What is the empirical formula of a compound that is 81.82% carbon and 18.18% hydrogen?

• C₃H₈

• CH₄

• C₂H₂

• C₄H₁₀

2 KClO₃ → 2 KCl + 3 O₂
How many moles of oxygen are produced when 6.7 moles of KClO₃ decompose completely?

• 6.7 mol
• 1.0 mol
• 10.1 mol
• 4.5 mol

Tags

NGSS.HS-PS1-7