.[BW] MAY 10-11 HONORS FINAL EXAM REVIEW

What is the first thing you must do to solve a stoichiometry problem?

• Write a Balanced Equation

• Write an Unbalanced Equation

• Convert grams to moles

• divide the mass by the molar mass

KNO₃ --> KNO₂ + O₂

What coefficients are needed to balance the reaction?

• 2, 2, 1

• 2, 3, 2

• 1, 3, 1

Tags

NGSS.HS-PS1-7

 The equation for Percent Yield:

Theoretical = Predicted

Actual = Experimental

• (actual divided by theoretical) X 100

• (actual - theoretical)/ theoretical X 100

• (theoretical divided by actual) X 100

2H₂   +   O₂  →  2H₂O

How many moles of water can be produced if 8 moles H₂ are used?

• 8

• 2

• 4

• 1

• 16

Tags

NGSS.MS-PS1-5

2H₂  +   O₂  →  2H₂O

How many moles of oxygen are consumed if 8 moles H₂ are used?

• 4

• 2

• 6

• 8

• 16

Tags

NGSS.HS-PS1-7

What is a Limiting Reagent?

• speeds up a reaction

• what you have left over

• what you run out of first

• slows down a reaction

What is a Excess Reagent?

• what you have left over

• amount you end with

• what you run out of first

• what you start with

You need 2 pieces of bread, 1 tablespoon of peanut butter and 2 tablespoons of jelly to make a sandwich.  If you have 10 pieces of bread, 4 tablespoons of peanut butter and 20 tablespoons of jelly, what is the limiting reactant?

• peanut butter

• bread

• jelly

• sandwich

Tags

NGSS.MS-PS1-2

For the Balanced Reaction: 3 Mg + 1 Fe₂O₃ → 3 MgO + 2 Fe

What is the Ratio of moles of Mg to moles Fe?

• 3:2

• 2:3

• 3:1

• 1:3

• 3:3

Tags

NGSS.HS-PS1-7

When does a chemical reaction stop?

• When the limiting reactant is used up

• When the lab is finished

• When the excess reactant is used up

• Chemical reactions never stop

• When the catalyst is used up