Limiting Reagent: 50g 0.5M HCl & NaOH-Calc # Mole

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The discussion focuses on determining the limiting reagent between 50g of 0.5M HCl and 50g of 0.5M NaOH in a neutralization reaction. The reaction follows the equation HCl + NaOH -> NaCl + water, with a 1:1 molar ratio of HCl to NaOH. To find the limiting reagent, one must calculate the number of moles by dividing the mass of each solution by its molar mass. Since the concentrations are given in molarity, the density of the solutions is needed to accurately convert the mass of the solutions to moles. Understanding the limiting reagent is crucial for calculating the enthalpy change of the reaction.
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Limiting reagent?

If there are 50g of 0.5M(molarity) HCl and 50g of 0.5M(molarity) NaOH which are allowed to react, which one is the limiting reagent? How to calculate the number of mole of limiting reagent?
 
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number of moles equals the mass of the substance divided by its molar mass.

Here are some questions for you:

1. What is a limiting reagent?
2. What reaction occurs?
3. In what ratio does it occur?
 
It should be neutralization, where HCl + NaOH ->NaCl + water.

From the equation, the ratio of HCl:NaOH =1:1

Since what i interested in is the enthalpy change of the reaction, so i need to know the number of mole of limiting reagent(the one which is lower in quantity, either HCl or NaOH).

Now i only got the masses of HCl(0.5M) and NaOH(0.5M) in solution, how can i obtain the number of mole of these 2 solution to compare their number of moles?
 
Do you mean 50g of 0.5M solution? If so, you need solution densities to proceed. These are tabelarized.
 
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