stoichiometry

How many particles are in 13.5 grams of Beryllium?

• 1.5 particles
• 9 particles
• 4x10²³ particles
• 9x10²³ particles

B₂H₆ + 3O₂ -->2 HBO₂ + 2 H₂O
 What mass of O₂ will be needed to burn 36.1 g of B₂H₆?

• 13.8 g O₂
• 3.86 mol of O₂
• 124 g O₂

Tags

NGSS.HS-PS1-7

In a lab, a scientist calculate he should produce 12.3 grams of product in his experiment. When he is finished collecting his product it weighs 10.1 grams. What is his percent yield?

• 82%
• 0.82%
• 10.1 %
• 100%

Tags

NGSS.HS-PS1-7

What is the percent yield of the following reaction if 145g of P₂O₅ reacts with 40 grams of water, but you only collected 112 grams of phosphoric acid? 3 H₂O + P₂O₅ -> 2H₃PO₄

• 80%
• 85%
• 77%
• 58%

Tags

NGSS.HS-PS1-7

If a chemist calculates the maximum amount of product that could be obtained in a chemical reaction, he or she is calculating the

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

Tags

NGSS.HS-PS1-7

SiO₂ + 3C → SiC + 2CO

I need to add 8 moles of Carbon to the reaction. How many grams of Carbon should I weigh?

• 96 g

• 0.67 g

• 2.67 g

• 48 g

What is a Excess Reagent?

• amount you end with
• what you run out of first
• what you have left over
• what you start with

Tags

NGSS.HS-PS1-7

A chemist interested in the efficiency of a chemical reaction would calculate the

• mole ratio
• rate of reaction
• percent yield
• energy released

Tags

NGSS.HS-PS1-4

NGSS.HS-PS1-5

When does a chemical reaction stop?

• When the lab is finished
• When the excess reactant is used up
• When the limiting reactant is used up
• Chemical reactions never stop

If you predicted that 1.5 moles of Magnessium are used in a reaction, and you have 2.0 moles of Magnessium, what type of reactant is Magnessium?

• Limiting Reactant
• Excess Reactant
• Fast Reacter
• Non-Reactant

Tags

NGSS.HS-PS1-7