Moles Of Sulfur Needed For 15.0 Moles Of SO2

Dec 1, 2025 by Admin 45 views

Understanding stoichiometry is crucial in chemistry, and this article will guide you through a problem involving the balanced equation for the formation of sulfur dioxide ( $SO_2$ ). We'll determine how many moles of sulfur ( $S$ ) are needed to produce 15.0 moles of $SO_2$ . Let's dive in!

Understanding the Balanced Equation

The balanced equation provided is:

$S + O_2 \rightarrow SO_2$

This equation tells us that one mole of sulfur ( $S$ ) reacts with one mole of oxygen ( $O_2$ ) to produce one mole of sulfur dioxide ( $SO_2$ ). The coefficients in front of each chemical formula represent the molar ratios of the reactants and products. In this case, the ratio of $S$ to $SO_2$ is 1:1.

Stoichiometry is all about these quantitative relationships in chemical reactions. By understanding the balanced equation, we can predict the amount of reactants needed or products formed in a chemical reaction. It's like a recipe – if you know the ingredients and their proportions, you can predict the final dish!

Applying the Molar Ratio

Since the molar ratio of $S$ to $SO_2$ is 1:1, it means that for every one mole of $SO_2$ produced, one mole of $S$ is required. Therefore, if we want to produce 15.0 moles of $SO_2$ , we will need 15.0 moles of $S$ . It's a direct relationship, making the calculation straightforward.

Step-by-Step Calculation

Identify the given quantity: We want to produce 15.0 moles of $SO_2$ .
Use the molar ratio: From the balanced equation, 1 mole of $S$ produces 1 mole of $SO_2$ .
Calculate the required amount of $S$ : Since the ratio is 1:1, we need 15.0 moles of $S$ to produce 15.0 moles of $SO_2$ .

Therefore, the answer is 15.0 mol of sulfur.

Why This Matters

Understanding stoichiometric relationships is essential in various fields, including:

Industrial Chemistry: In industrial processes, knowing the exact amounts of reactants needed to produce a desired amount of product is crucial for efficiency and cost-effectiveness. Overusing or underusing reactants can lead to waste and reduced yields.
Environmental Science: Stoichiometry helps in understanding and controlling pollution. For example, in the context of sulfur dioxide, understanding how it forms and how it can be removed from emissions is vital for environmental protection.
Research and Development: In research, scientists often need to synthesize new compounds or analyze reaction pathways. Stoichiometry provides the foundation for these investigations, allowing researchers to make accurate predictions and interpretations.
Everyday Life: Believe it or not, stoichiometry even has applications in everyday life. When you're baking, you're essentially using stoichiometry to ensure the right proportions of ingredients for your cake or cookies!

Common Mistakes to Avoid

When working with stoichiometry, it's easy to make mistakes if you're not careful. Here are some common pitfalls to watch out for:

Not Balancing the Equation: Always ensure the chemical equation is balanced before performing any stoichiometric calculations. An unbalanced equation will lead to incorrect molar ratios and, consequently, incorrect results.
Using the Wrong Molar Mass: Make sure you're using the correct molar masses for all the substances involved. Molar mass is the mass of one mole of a substance and is usually found on the periodic table.
Incorrectly Applying the Molar Ratio: Double-check that you're using the correct molar ratio from the balanced equation. This is the most critical step in stoichiometric calculations.
Ignoring Units: Always include units in your calculations and make sure they cancel out correctly. Units can be a lifesaver in preventing errors.

Practice Problems

To solidify your understanding of stoichiometry, let's work through a couple of practice problems.

Problem 1:

How many moles of hydrogen ( $H_2$ ) are needed to react completely with 3 moles of nitrogen ( $N_2$ ) in the following reaction?

$N_2 + 3H_2 \rightarrow 2NH_3$

Solution:

From the balanced equation, we see that 1 mole of $N_2$ reacts with 3 moles of $H_2$ . Therefore, the molar ratio of $N_2$ to $H_2$ is 1:3. To react with 3 moles of $N_2$ , we need:

3 moles $N_2$ * (3 moles $H_2$ / 1 mole $N_2$ ) = 9 moles $H_2$

Problem 2:

If 4 moles of $CO_2$ are produced, how many moles of $O_2$ were reacted? Given the reaction:

$2CO + O_2 \rightarrow 2CO_2$

Solution:

The balanced equation shows that 1 mole of $O_2$ produces 2 moles of $CO_2$ . Thus, the molar ratio of $O_2$ to $CO_2$ is 1:2. If 4 moles of $CO_2$ are produced, then:

4 moles $CO_2$ * (1 mole $O_2$ / 2 moles $CO_2$ ) = 2 moles $O_2$

Conclusion

In summary, to produce 15.0 moles of sulfur dioxide ( $SO_2$ ) according to the balanced equation $S + O_2 \rightarrow SO_2$ , you need 15.0 moles of sulfur ( $S$ ). Understanding stoichiometry and molar ratios is fundamental in chemistry, allowing us to make accurate predictions and calculations in chemical reactions. By mastering these concepts and avoiding common mistakes, you'll be well-equipped to tackle more complex problems in chemistry.

So next time you're faced with a stoichiometric problem, remember to balance the equation, identify the molar ratios, and apply them correctly. You got this!

Therefore, the correct answer is:

C. 15.0 mol