Limiting and Excess Reactants and Percent Yield

The limiting reactant

• .
• is used up first
• is the reactant that is left over
• .

Tags

NGSS.HS-PS1-7

The excess reactant

• .
• is used up first
• is the reactant that is left over
• .

1 Body + 4 Tires --> 1 car
How many cars can you make with 92 tires and 34 bodies? 

• 23
• 34
• 68
• 46

1 Body + 4 Tires --> 1 car
How many cars can you make with 92 tires and 34 bodies? 
In this senario the tires would be the _____________  reactant. 

• Limiting 
• Excess 

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

When the limiting reactant is used up, what happens?

• the reaction speeds up
• the reaction slows down
• the reaction moves to its 2nd stage
• the reaction stops

What are the correct steps for determining the limiting reactant?

• divide each reactant by its molar mass and look for the smallest number
• balance the chemical equation and look for the smallest coefficient
• divide the moles of each reactant by its coefficient and look for the smallest number
• divide each reactant by Avogadro's number and look for the smallest number

What is the measured amount of a product obtained from a chemical reaction?

• mole ratio
• theoretical yield
• percentage yield
• actual yield

True or False?
A chemical reaction stops before the limiting reagent is used up.

• True
• False

When does a reaction stop?

• When it wants to
• When both the limiting and excess reactants are gone
• When all the excess reactant has been consumed
• When all the limiting reactant has been consumed

Tags

NGSS.HS-PS1-7

What is the limiting reactant if 10 moles of NH₃  react  with 30.0 moles of NO?
4NH₃+6NO --> 5N₂ + 6H₂O

• NH₃
• NO
• N₂
• water

Tags

NGSS.HS-PS1-7