Stoichometry, Limiting Reagent and Excess Reagent

Mia and David are working on a chemistry experiment. They mix 12 moles of P₄  with 15 moles of O₂. According to the reaction P₄ + 3O₂ --> P₄O₆ , what is the limiting reactant?

• P₄

• O₂

• P₄O₆ 

• none of the above

Priya conducted an experiment in her chemistry lab.
Theoretical yield = 73g
Actual yield = 62g
Calculate the percent yield.

• 1.16%

• 116%

• 85%

• 76%

Tags

NGSS.HS-PS1-7

Maya and Lily are working on a chemistry project. They need to find out how many grams of ammonia (NH₃) can be produced from the reaction of 28 g of nitrogen gas and 25 grams of hydrogen gas? 

• 43 g

• 34 moles

• 25 grams

• 34 grams

Tags

NGSS.HS-PS1-7

Priya and William are conducting a chemistry experiment. They react equal amounts of 200 g each of silver nitrate and sodium phosphate. How many grams of silver phosphate are produced? 
3AgNO₃  + Na₃(PO₄)  --->  Ag₃(PO₄)  + 3NaNO₃

• 164 g

• 64 g

• 146 g

• 164 moles

Tags

NGSS.HS-PS1-7

Emma and Michael are conducting a chemistry experiment. Identify the limiting reagent when 6.00 g HCl combines with 5.00 g Mg to form MgCl₂.
a.  Mg +  2HCl --> MgCl₂  +  H₂   
b.  a.  Mg +  2HCl --> MgCl₂  +  H₂   

• Mg

• H₂

• MgCl₂

• HCl

Tags

NGSS.HS-PS1-7

Oliver and Kai are conducting an experiment using the equation 2 Al + 3 Cl₂ ---> 2 AlCl₃. If they use 2 moles of aluminum and 2 moles of chlorine, identify the limiting reactant.

• AlCl₃

• Cl₂

• Al

Maya and Charlotte are conducting an experiment using the equation 2 Al + 3 Cl₂ ---> 2 AlCl₃. If they use 2 moles of aluminum and 2 moles of chlorine, identify the limiting reactant.

• AlCl₃

• Cl₂

• Al

Tags

NGSS.HS-PS1-7

Zoe and Charlotte are working on a chemistry experiment. They mix 10 moles of NH₃ with 30.0 moles of NO.
4NH₃+6NO --> 5N₂ + 6H₂O. What is the limiting reactant?

• NH₃

• NO

• N₂

• water

Tags

NGSS.HS-PS1-7

Scarlett and Emma are making S'mores. The formula to make S'mores is:

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

• 5

• 4

• 8

• 42

Sophia is conducting a chemistry experiment. For the Balanced Reaction: 3 Mg + 1 Fe₂O₃ → 3 MgO + 2 Fe; What is the Ratio of moles of Mg to moles Fe?

• 3mol Mg / 2 mol Fe

• 2 mol Mg/ 3 mol Fe

• 1 mol Fe/ 2 mol Fe

• 3 mol MgO / 2 mol Fe