4 G Of Magnesium Is Reacted With A Hydrochloric Acid Solution That Contains 5.48 G Of The Acid.$\[ \text{Mg(s)} + 2 \text{HCl(aq)} \rightarrow \text{MgCl}_2\text{(aq)} + \text{H}_2\text{(g)} \\]Which Of The Reactants Is The Limiting Reagent?

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Introduction

In a chemical reaction, the limiting reagent is the reactant that is consumed first and determines the amount of product that can be formed. In this article, we will determine the limiting reagent in a reaction between magnesium (Mg) and hydrochloric acid (HCl). The reaction is as follows:

Mg(s)+2HCl(aq)→MgCl2(aq)+H2(g){ \text{Mg(s)} + 2 \text{HCl(aq)} \rightarrow \text{MgCl}_2\text{(aq)} + \text{H}_2\text{(g)} }

The Chemical Equation

The balanced chemical equation for the reaction is:

Mg(s)+2HCl(aq)→MgCl2(aq)+H2(g){ \text{Mg(s)} + 2 \text{HCl(aq)} \rightarrow \text{MgCl}_2\text{(aq)} + \text{H}_2\text{(g)} }

This equation shows that 1 mole of magnesium reacts with 2 moles of hydrochloric acid to produce 1 mole of magnesium chloride and 1 mole of hydrogen gas.

Calculating the Number of Moles of Magnesium

To determine the limiting reagent, we need to calculate the number of moles of each reactant. We are given that 4 g of magnesium is reacted with a hydrochloric acid solution that contains 5.48 g of the acid.

First, we need to calculate the number of moles of magnesium. The atomic mass of magnesium is 24.31 g/mol.

# Calculate the number of moles of magnesium
magnesium_mass = 4  # in g
magnesium_atomic_mass = 24.31  # in g/mol
magnesium_moles = magnesium_mass / magnesium_atomic_mass
print(f"The number of moles of magnesium is {magnesium_moles:.2f} mol")

Calculating the Number of Moles of Hydrochloric Acid

Next, we need to calculate the number of moles of hydrochloric acid. The molar mass of hydrochloric acid is 36.46 g/mol.

# Calculate the number of moles of hydrochloric acid
hydrochloric_acid_mass = 5.48  # in g
hydrochloric_acid_molar_mass = 36.46  # in g/mol
hydrochloric_acid_moles = hydrochloric_acid_mass / hydrochloric_acid_molar_mass
print(f"The number of moles of hydrochloric acid is {hydrochloric_acid_moles:.2f} mol")

Determining the Limiting Reagent

Now that we have calculated the number of moles of each reactant, we can determine the limiting reagent. The limiting reagent is the reactant that is consumed first and determines the amount of product that can be formed.

In this reaction, 1 mole of magnesium reacts with 2 moles of hydrochloric acid. Therefore, the number of moles of hydrochloric acid required to react with 4 g of magnesium is:

# Calculate the number of moles of hydrochloric acid required
magnesium_moles = 4 / 24.31  # in mol
hydrochloric_acid_moles_required = 2 * magnesium_moles
print(f"The number of moles of hydrochloric acid required is {hydrochloric_acid_moles_required:.2f} mol")

Comparing the calculated number of moles of hydrochloric acid required with the actual number of moles of hydrochloric acid present, we can determine the limiting reagent.

# Determine the limiting reagent
if hydrochloric_acid_moles_required > hydrochloric_acid_moles:
    print("Magnesium is the limiting reagent.")
else:
    print("Hydrochloric acid is the limiting reagent.")

Conclusion

In this article, we have determined the limiting reagent in a reaction between magnesium and hydrochloric acid. We calculated the number of moles of each reactant and compared it with the number of moles required to react with 4 g of magnesium. Based on the comparison, we determined that hydrochloric acid is the limiting reagent.

Limiting Reagent Calculation

Magnesium Limiting Reagent

If the number of moles of hydrochloric acid required is greater than the actual number of moles of hydrochloric acid present, then magnesium is the limiting reagent.

Hydrochloric Acid Limiting Reagent

If the number of moles of hydrochloric acid required is less than or equal to the actual number of moles of hydrochloric acid present, then hydrochloric acid is the limiting reagent.

Limiting Reagent Example

Let's consider an example where 4 g of magnesium is reacted with a hydrochloric acid solution that contains 5.48 g of the acid.

# Calculate the number of moles of magnesium
magnesium_mass = 4  # in g
magnesium_atomic_mass = 24.31  # in g/mol
magnesium_moles = magnesium_mass / magnesium_atomic_mass

# Calculate the number of moles of hydrochloric acid
hydrochloric_acid_mass = 5.48  # in g
hydrochloric_acid_molar_mass = 36.46  # in g/mol
hydrochloric_acid_moles = hydrochloric_acid_mass / hydrochloric_acid_molar_mass

# Calculate the number of moles of hydrochloric acid required
magnesium_moles = 4 / 24.31  # in mol
hydrochloric_acid_moles_required = 2 * magnesium_moles

# Determine the limiting reagent
if hydrochloric_acid_moles_required > hydrochloric_acid_moles:
    print("Magnesium is the limiting reagent.")
else:
    print("Hydrochloric acid is the limiting reagent.")

Limiting Reagent Formula

The limiting reagent formula is:

Limiting Reagent=Moles of Reactant 1Moles of Reactant 2{ \text{Limiting Reagent} = \frac{\text{Moles of Reactant 1}}{\text{Moles of Reactant 2}} }

Where Reactant 1 is the reactant that is consumed first and Reactant 2 is the reactant that is present in excess.

Limiting Reagent Conclusion

Introduction

In our previous article, we discussed the concept of limiting reagent in a chemical reaction. We calculated the number of moles of each reactant and determined that hydrochloric acid is the limiting reagent in a reaction between magnesium and hydrochloric acid. In this article, we will answer some frequently asked questions related to limiting reagent.

Q: What is the limiting reagent?

A: The limiting reagent is the reactant that is consumed first and determines the amount of product that can be formed.

Q: How do I determine the limiting reagent?

A: To determine the limiting reagent, you need to calculate the number of moles of each reactant and compare it with the number of moles required to react with the given amount of reactant.

Q: What is the formula for calculating the limiting reagent?

A: The formula for calculating the limiting reagent is:

Limiting Reagent=Moles of Reactant 1Moles of Reactant 2{ \text{Limiting Reagent} = \frac{\text{Moles of Reactant 1}}{\text{Moles of Reactant 2}} }

Where Reactant 1 is the reactant that is consumed first and Reactant 2 is the reactant that is present in excess.

Q: What is the difference between a limiting reagent and an excess reagent?

A: A limiting reagent is the reactant that is consumed first and determines the amount of product that can be formed. An excess reagent is the reactant that is present in excess and is not consumed during the reaction.

Q: Can a reactant be both a limiting reagent and an excess reagent?

A: No, a reactant cannot be both a limiting reagent and an excess reagent. A reactant is either a limiting reagent or an excess reagent, but not both.

Q: How do I know if a reactant is a limiting reagent or an excess reagent?

A: To determine if a reactant is a limiting reagent or an excess reagent, you need to calculate the number of moles of each reactant and compare it with the number of moles required to react with the given amount of reactant.

Q: What is the significance of the limiting reagent in a chemical reaction?

A: The limiting reagent is significant in a chemical reaction because it determines the amount of product that can be formed. The limiting reagent is the reactant that is consumed first and determines the amount of product that can be formed.

Q: Can the limiting reagent be changed during a chemical reaction?

A: No, the limiting reagent cannot be changed during a chemical reaction. The limiting reagent is determined by the initial amounts of reactants and cannot be changed during the reaction.

Q: How do I calculate the number of moles of a reactant?

A: To calculate the number of moles of a reactant, you need to know the mass of the reactant and its molar mass. The number of moles of a reactant can be calculated using the following formula:

Number of Moles=Mass of ReactantMolar Mass of Reactant{ \text{Number of Moles} = \frac{\text{Mass of Reactant}}{\text{Molar Mass of Reactant}} }

Q: What is the molar mass of a reactant?

A: The molar mass of a reactant is the mass of one mole of the reactant. The molar mass of a reactant can be calculated by adding the atomic masses of its constituent atoms.

Q: How do I calculate the molar mass of a reactant?

A: To calculate the molar mass of a reactant, you need to know the atomic masses of its constituent atoms. The molar mass of a reactant can be calculated by adding the atomic masses of its constituent atoms.

Conclusion

In conclusion, the limiting reagent is a crucial concept in chemistry that determines the amount of product that can be formed in a chemical reaction. We have answered some frequently asked questions related to limiting reagent and provided formulas and examples to help you understand the concept better.