Concept:This is a classic mass-to-mole stoichiometry problem. First write the balanced neutralization equation, convert the given mass to moles, and apply the molar ratio.
Formula:$$ \text{HCl} + \text{NaOH} \rightarrow \text{NaCl} + \text{H}_2\text{O} $$
Solution:- The balanced neutralization equation shows a 1:1 ratio. 1 mole of HCl reacts to form 1 mole of NaCl.
- Calculate the moles of the given HCl:
- Molar mass of HCl = \( 1 \text{ (H)} + 35.5 \text{ (Cl)} = 36.5 \text{ g/mol} \).
- Moles of HCl = \( 16.5 \text{ g} / 36.5 \text{ g/mol} \).
- \( 16.5 / 36.5 \approx 0.452 \text{ moles} \).
- Because of the 1:1 ratio, 0.452 moles of HCl will strictly produce 0.452 moles of NaCl.
Why other options are incorrect:- 0.252, 0.652, 0.852: These are incorrect mathematical quotients resulting from dividing 16.5 by wrong molar mass values (such as using Cl=35 instead of 35.5, or pure arithmetic failure).
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