Question

which choice identifies the correct limiting reactant and correct reasoning?
2nacl + pb(no₃)₂ → 2nano₃ + pbcl₂
15.3 g nacl theoretically yields 36.4 g pbcl₂.
60.8 g pb(no₃)₂ theoretically yields 51.1 g pbcl₂.
pb(no₃)₂ because it has the higher theoretical yield
pb(no₃)₂ because it has the higher initial mass
nacl because it has the lower theoretical yield
nacl because it has the lower initial mass

Explanation:

To determine the limiting reactant, we compare the theoretical yields of the product (\(PbCl_2\)) from each reactant. The limiting reactant is the one that produces the smaller amount of product because it will be completely consumed first, limiting the amount of product formed.

• \(NaCl\) produces \(36.4\space g\) of \(PbCl_2\).
• \(Pb(NO_3)_2\) produces \(51.1\space g\) of \(PbCl_2\).

Since \(NaCl\) produces a lower theoretical yield of \(PbCl_2\), it is the limiting reactant.

Now let's analyze the options:

• Option 1: Incorrect. A higher theoretical yield means the reactant is in excess, not limiting.
• Option 2: Incorrect. Initial mass does not determine the limiting reactant; it's about the amount of product formed.
• Option 3: Correct. \(NaCl\) has the lower theoretical yield, so it is the limiting reactant.
• Option 4: Incorrect. Initial mass is not the factor for determining the limiting reactant.

Answer:

C. NaCl because it has the lower theoretical yield (assuming the third option is labeled C; if the original options have different labels, adjust accordingly to match the option with "NaCl because it has the lower theoretical yield")