Final answer:
To neutralize 1.5 moles of sodium hydroxide, 1.5 moles of hydrochloric acid are needed based on the 1:1 mole ratio from the balanced chemical equation for their neutralization reaction.The corrrect option is 3.
Step-by-step explanation:
The chemical reaction between hydrochloric acid (HCl) and sodium hydroxide (NaOH) is:
HCl (aq) + NaOH (aq) → NaCl (aq) + H₂O (l)
To find the number of moles of hydrochloric acid needed to neutralize 1.5 moles of sodium hydroxide, we use the concept of equivalent masses. The equivalent mass of an acid or base is the mass that provides one mole of hydrogen ions (H⁺) or hydroxide ions (OH⁻), respectively.
The equivalent mass of HCl is 36 grams, and the equivalent mass of NaOH is 40 grams. Therefore, we can calculate the number of moles of HCl needed to neutralize 1.5 moles of NaOH as follows:
1. Calculate the number of moles of NaOH:
1.5 mol NaOH = 1.5 × 40 g/mol NaOH = 60 g NaOH
2. Calculate the number of moles of HCl required to neutralize this amount of NaOH:
60 g NaOH requires 60 g HCl to neutralize it completely. Since the equivalent mass of HCl is 36 g, we can calculate the number of moles as follows:
60 g HCl / 36 g/mol HCl = 1.67 mol HCl
However, since we cannot have a fractional mole, we round up to two significant figures, which gives us 2 mol HCl.
3. Therefore, option (3) is correct, and we need 3 moles of hydrochloric acid to neutralize 1.5 moles of sodium hydroxide.The corrrect option is 3.