Questions: Question 1 (5 points)
Review question #1-1: Consider the following redox reaction:
Cu(s) + 4 HNO3(aq) à Cu(NO3)2(aq) + 2 NO2(g) + 2 H2O(l)
If 5.48 g of Cu are allowed to react with excess HNO3, what is the theoretical yield (g) of Cu(NO3)2 in grams?
Transcript text: Question 1 (5 points)
Review question \#1-1: Consider the following redox reaction:
\[
\mathrm{Cu}(\mathrm{~s})+4 \mathrm{HNO}_{3}(\mathrm{aq}) \text { à } \mathrm{Cu}\left(\mathrm{NO}_{3}\right)_{2}(\mathrm{aq})+2 \mathrm{NO}_{2}(\mathrm{~g})+2 \mathrm{H}_{2} \mathrm{O}(\mathrm{l})
\]
If 5.48 g of Cu are allowed to react with excess $\mathrm{HNO}_{3}$, what is the theoretical yield (g) of $\mathrm{Cu}\left(\mathrm{NO}_{3}\right)_{2}$ in grams?
Solution
Solution Steps
Step 1: Determine Molar Mass of Copper (Cu)
The molar mass of copper (Cu) is approximately \( 63.55 \, \text{g/mol} \).
Step 2: Calculate Moles of Copper
Use the formula:
\[
\text{moles of Cu} = \frac{\text{mass of Cu}}{\text{molar mass of Cu}}
\]
Given mass of Cu = 5.48 g, calculate:
\[
\text{moles of Cu} = \frac{5.48 \, \text{g}}{63.55 \, \text{g/mol}}
\]
Step 3: Use Stoichiometry to Find Moles of \(\mathrm{Cu}\left(\mathrm{NO}_{3}\right)_{2}\)
From the balanced equation, 1 mole of Cu produces 1 mole of \(\mathrm{Cu}\left(\mathrm{NO}_{3}\right)_{2}\).
Therefore, moles of \(\mathrm{Cu}\left(\mathrm{NO}_{3}\right)_{2}\) = moles of Cu.
Step 4: Determine Molar Mass of \(\mathrm{Cu}\left(\mathrm{NO}_{3}\right)_{2}\)
Total molar mass of \(\mathrm{Cu}\left(\mathrm{NO}_{3}\right)_{2}\) = \( 63.55 + 28.02 + 96.00 = 187.57 \, \text{g/mol} \)
Step 5: Calculate Theoretical Yield of \(\mathrm{Cu}\left(\mathrm{NO}_{3}\right)_{2}\)
Use the formula:
\[
\text{mass of } \mathrm{Cu}\left(\mathrm{NO}_{3}\right)_{2} = \text{moles of } \mathrm{Cu}\left(\mathrm{NO}_{3}\right)_{2} \times \text{molar mass of } \mathrm{Cu}\left(\mathrm{NO}_{3}\right)_{2}
\]
Substitute the values to find the theoretical yield.