ALEKS: Writing the net equation for a sequence of reactions

Summary

In this video, viewers learn how to solve the Alex problem of writing the net equation for a sequence of reactions. The instructor demonstrates the process by combining two balanced chemical equations, focusing on the common molecule, NH3. Steps include equalizing stoichiometric coefficients, combining reactants and products, simplifying the equation by removing common components, and restoring physical states. Finally, the importance of verifying that the resulting equation remains balanced is emphasized, ensuring clarity and accuracy in chemical representation.

Takeaways

• 😀 The objective is to write a net equation by combining two balanced chemical equations.
• 🔍 Identify a common molecule between the products of the first equation and the reactants of the second.
• ⚖️ Ensure the stoichiometric coefficients for the common molecule are the same in both equations.
• ✖️ To match coefficients, multiply the entire equation by a necessary factor while maintaining balance.
• ➕ Combine the reactants from both equations on the left side of the new equation.
• ➡️ Write out all products on the right side of the new equation after combining.
• ✂️ Simplify the equation by removing species that appear on both sides in the same form.
• 🔄 Restore the states of matter (solid, liquid, gas, aqueous) to the final equation.
• ✔️ Verify that the final equation is balanced by counting atoms of each element on both sides.
• ✅ The simplification process should not alter the balance of the equation, ensuring accuracy.

Q & A

What is the main objective of the video?

The main objective is to show how to combine two balanced chemical equations into a single net equation.

What is the first step in solving the Alex problem?

The first step is to identify the common molecule between the products of the first equation and the reactants of the second equation.

Which molecule is identified as common in the example provided?

The common molecule identified in the example is NH3.

How do you ensure that the stoichiometric coefficients are the same for the common molecule?

You adjust the stoichiometric coefficients by multiplying the entire equation by a factor that makes the coefficients equal.

What do you do if the stoichiometric coefficients of the common molecule are different?

If the coefficients are different, you need to multiply both equations by factors that will equalize the coefficients for the common molecule.

What is the process after equalizing the coefficients?

After equalizing the coefficients, you combine the reactants and products from both equations into a new equation.

What should you look for when simplifying the new equation?

You should look for molecules present on both sides of the equation that can be simplified or removed.

Why is it important to reinsert the states of matter in the final equation?

Reinserting the states of matter is important for clarity and to ensure that the equation accurately represents the conditions of the reactions.

How can you verify that the new equation is balanced?

You can verify that the new equation is balanced by counting the number of atoms of each element on both sides and ensuring they match.

What is the significance of maintaining balance in the chemical equations?

Maintaining balance is crucial because it reflects the law of conservation of mass, indicating that the same number of each type of atom exists on both sides of the equation.