Discover a wealth of knowledge at Westonci.ca, where experts provide answers to your most pressing questions. Connect with a community of experts ready to help you find solutions to your questions quickly and accurately. Explore comprehensive solutions to your questions from a wide range of professionals on our user-friendly platform.

Gas Stoichiometry at STP

The balanced chemical equation is:
[tex]\[ 2 C_2H_2(g) + 5 O_2(g) \rightarrow 4 CO_2(g) + 2 H_2O(g) \][/tex]

You want to calculate the number of moles of [tex]\( H_2O \)[/tex] that form from [tex]\( 13.5 \, L \, O_2 \)[/tex], assuming the reaction is at STP.

Use the dimensional analysis below to set up the two-step calculation.

[tex]\[
\begin{array}{c|c|c}
13.5 \, L \, O_2 & \rightarrow & \text{moles of } O_2 \\
& \rightarrow & \text{moles of } H_2O
\end{array}
\][/tex]

Ratios:

1. [tex]\(\text{Ratio 1}\)[/tex]: [tex]\( \frac{\text{Moles of } O_2}{22.4 \, L} \)[/tex] (molar volume at STP)
2. [tex]\(\text{Ratio 2}\)[/tex]: [tex]\( \frac{\text{Moles of } H_2O}{\text{Moles of } O_2} \)[/tex] (from the balanced equation)


Sagot :

Let's solve this problem step-by-step using dimensional analysis as requested.

1. Step 1: Calculate the number of moles of [tex]\( O_2 \)[/tex] given: We know that at STP (standard temperature and pressure), 1 mole of any gas occupies 22.4 liters.

[tex]\[ \text{Given volume of oxygen} = 13.5 \text{ L} \][/tex]

We use the molar volume to convert this to moles of [tex]\( O_2 \)[/tex]:

[tex]\[ \text{Moles of } O_2 = \frac{\text{Volume of } O_2}{\text{Molar volume at STP}} = \frac{13.5 \text{ L}}{22.4 \text{ L/mol}} = 0.6026785714285715 \text{ mol} \][/tex]

2. Step 2: Use the stoichiometric relationship to find the moles of [tex]\( H_2O \)[/tex] produced: The balanced chemical equation shows the stoichiometric relationship between [tex]\( O_2 \)[/tex] and [tex]\( H_2O \)[/tex]:

[tex]\[ 2 C_2H_2(g) + 5 O_2(g) \rightarrow 4 CO_2(g) + 2 H_2O(g) \][/tex]

From the equation, 5 moles of [tex]\( O_2 \)[/tex] produce 2 moles of [tex]\( H_2O \)[/tex]. Therefore, the ratio between [tex]\( O_2 \)[/tex] and [tex]\( H_2O \)[/tex] is:

[tex]\[ \frac{\text{Moles of } H_2O}{\text{Moles of } O_2} = \frac{2}{5} \][/tex]

Now, using the moles of [tex]\( O_2 \)[/tex] calculated in Step 1:

[tex]\[ \text{Moles of } H_2O = \frac{2}{5} \times \text{Moles of } O_2 = \frac{2}{5} \times 0.6026785714285715 \approx 0.2410714285714286 \text{ mol} \][/tex]

Thus, the number of moles of [tex]\( H_2O \)[/tex] formed from 13.5 liters of [tex]\( O_2 \)[/tex] at STP is approximately 0.2410714285714286 moles.
Thanks for using our platform. We're always here to provide accurate and up-to-date answers to all your queries. Your visit means a lot to us. Don't hesitate to return for more reliable answers to any questions you may have. Find reliable answers at Westonci.ca. Visit us again for the latest updates and expert advice.