Given the following equation:

[tex]\[ Pb \left( SO_4 \right)_2 + 4 LiNO_3 \rightarrow Pb \left( NO_3 \right)_4 + 2 Li_2SO_4 \][/tex]

How many grams of lithium nitrate will be needed to make 125.0 grams of lithium sulfate, assuming that you have an adequate amount of lead (IV) sulfate to do the reaction?



Answer :

To find out how many grams of lithium nitrate (LiNO₃) are needed to produce 125.0 grams of lead (IV) nitrate [tex]\( \text{Pb(NO}_3\text{)}_4 \)[/tex] assuming that there is an adequate amount of lead (IV) sulfate [tex]\( \text{Pb(SO}_4\text{)}_2 \)[/tex], we need to follow a detailed, step-by-step approach using stoichiometry.

### Step 1: Molar Mass Calculation

First, let’s revise the molar masses of the compounds involved in the reaction:

- Molar mass of [tex]\( \text{Pb(NO}_3\text{)}_4 \)[/tex] = 455.24 g/mol
- Molar mass of [tex]\( \text{LiNO}_3 \)[/tex] = 68.94 g/mol

### Step 2: Convert Mass of [tex]\( \text{Pb(NO}_3\text{)}_4 \)[/tex] to Moles

Now, convert the given mass of [tex]\( \text{Pb(NO}_3\text{)}_4 \)[/tex] to moles:

[tex]\[ \text{Moles of }\text{Pb(NO}_3\text{)}_4 = \frac{\text{Mass of Pb(NO}_3\text{)}_4}{\text{Molar Mass of Pb(NO}_3\text{)}_4} = \frac{125.0 \text{ g}}{455.24 \text{ g/mol}} \approx 0.2746 \text{ mol} \][/tex]

### Step 3: Stoichiometric Calculation to Find Moles of LiNO₃ Needed

According to the balanced chemical equation, 1 mole of [tex]\( \text{Pb(SO}_4\text{)}_2 \)[/tex] reacts with 4 moles of [tex]\( \text{LiNO}_3 \)[/tex] to produce 1 mole of [tex]\( \text{Pb(NO}_3\text{)}_4 \)[/tex].

Therefore, for the amount of [tex]\( \text{Pb(NO}_3\text{)}_4 \)[/tex] given (0.2746 mol), we can use the stoichiometric ratio (1:4) to find the moles of [tex]\( \text{LiNO}_3 \)[/tex] required:

[tex]\[ \text{Moles of LiNO}_3 = 4 \times \text{Moles of Pb(NO}_3\text{)}_4 \approx 4 \times 0.2746 = 1.0983 \text{ mol} \][/tex]

### Step 4: Convert Moles of LiNO₃ to Mass

Now, convert the moles of LiNO₃ to grams using its molar mass:

[tex]\[ \text{Mass of LiNO}_3 = \text{Moles of LiNO}_3 \times \text{Molar Mass of LiNO}_3 = 1.0983 \text{ mol} \times 68.94 \text{ g/mol} \approx 75.72 \text{ g} \][/tex]

### Conclusion

You will need approximately 75.72 grams of lithium nitrate [tex]\( \text{LiNO}_3 \)[/tex] to produce 125.0 grams of lead (IV) nitrate [tex]\( \text{Pb(NO}_3\text{)}_4 \)[/tex], assuming an adequate amount of lead (IV) sulfate [tex]\( \text{Pb(SO}_4\text{)}_2 \)[/tex].