One Step Stoichiometry

Which part of a reaction is used to calculate the molar ratio?

• Subscripts

• You don't use the reaction

• Coefficients of the Unbalanced Reaction

• Coefficients of the Balanced Reaction

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

Tags

NGSS.HS-PS1-7

How many moles of hydrogen gas are needed to react completely with 2.0 moles of nitrogen gas? What is the mole ratio of hydrogen gas to nitrogen gas?

• 1:3

• 3:1

• 1:2

• 2:1

Select the correct molar ratio taken from this balanced equation:

• 1 mol Al = 1 mol Al₂O₃

• 4 Al = 2 Al₂O₃

• 4 mol Al = 2 mol Al₂O₃

• 4 mol Al = 2 mol Al

Tags

NGSS.HS-PS1-7

The blue numbers in the image below represent ________

• I don't know, and don't want to try

• coefficients

• subscripts

• none of the answers are correct

What is the first step in completing a stoichiometry problem?

• Calculating the Molar Mass

• Writing the Balanced Equation

• Write your Final Answer

• Use the Railroad Track Method to Calculate the Answer

What conversion factor do you always use in stoichiometry problems?

• reciprocal of the molar mass of a substance

• molar mass of a substance

• mole ratio

• molar volume of a gas

What is the mole ratio of Aluminum to Oxygen in the chemical reaction: Al + O₂ --> Al₂O₃

• 1:1

• 2:3

• 4:2

• 4:3

• 3: 4

2Na + 2H₂O → 2NaOH+ H₂
How many grams of hydrogen are produced if 120 g of Na are available?

• 5.2 g

• 2.6 g

• 690 g

• 45 g

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