How to: Step by Step Stoichiometry

Multiple Choice

Which of the following is the correct first step when solving stoichiometry problems?

• Write the balanced chemical equation first

• Calculate the percent yield

• Identify spectator ions

• Report sources of loss

Multiple Select

Which of the following are key steps in solving stoichiometry problems, according to the key points provided?

• Write the balanced chemical equation

• Extract mole ratios from coefficients

• Convert quantities to moles

• Report sources of loss

Open Ended

Explain why the actual yield is usually lower than the theoretical yield in a chemical reaction.

Reorder

Describe the steps you would take to write a net ionic equation for a precipitation reaction.

• Write a balanced molecular equation with physical states.

• Identify soluble vs insoluble species; dissociate strong electrolytes.

• Write a complete ionic equation; cancel spectators to get net ionic.

• Check mass and charge balance and label reaction type.

1

2

3

4

• 1
• 2
• 3
• 4

Open Ended

Explain the process of determining the molecular formula from percent composition data.

Multiple Choice

Which of the following best describes a synthesis reaction?

• A single element replaces another in a compound

• Two or more simple substances combine to form one compound

• One compound breaks down into two or more substances

• Two aqueous ionic solutions exchange ions

Multiple Select

Select all the correct steps involved in the general problem-solving checklist for chemistry problems.

• Write givens, required, and equations

• Convert to moles or ions as appropriate

• Apply correct operation and perform arithmetic carefully

• Guess the answer based on intuition

Open Ended

Explain the difference between percent composition and percent yield, and describe a scenario where confusing the two could lead to an error in a chemistry calculation.

Multiple Choice

Which of the following is a common mistake that leads to incorrect net ionic equations?

• Not balancing the equation first

• Forgetting aqueous vs solid states

• Rounding too early

• Confusing percent composition with percent yield

Open Ended

After learning about stoichiometry problems, what is one question you still have or a topic you would like to explore further?

Open Ended

What is one key concept you learned about stoichiometry, net ionic equations, empirical & molecular formulas, or reaction types in this lesson?

Labelling

MATCH THE EMPIRICAL AND MOLECULAR FORMULAS.

Drag labels to their correct position on the image

Labelling

MATCH THE EMPIRICAL AND MOLECULAR FORMULAS.

Drag labels to their correct position on the image

Multiple Choice

How many atoms of carbon are used to make a molecule of sugar, C₁₂H₂₂O₁₁?

• 12
• 22
• 11
• Sugar is not a molecule

Labelling

Label the reactants and products in the chemical equation shown.

Drag labels to their correct position on the image

Products

Reactants

Labelling

Drag the following labels to show the equation for percent yield.

Drag labels to their correct position on the image

Theoretical

100

Actual

Multiple Choice

If 23 g KCl are obtained,

what is the percent yield for the reaction?

• 44%

• 102%

• 98%

• 43%

Hotspot

Click on the products coefficient.

Dropdown

What type of chemical reaction is A? ​

Select answer