1. Write the Balanced Chemical Equation:
The balanced chemical equation for this reaction is:
2 NaOH (aq) + CuCl₂ (aq) → Cu(OH)₂ (s) + 2 NaCl (aq)
2. Understand Limiting Reagent:
The limiting reagent is the reactant that gets completely consumed first in a chemical reaction, thus limiting the amount of product that can be formed.
3. Determine the Moles of Each Reactant:
* You'll need to know the specific masses or concentrations of NaOH and CuCl₂ to calculate the moles. Let's assume you have:
* X grams of NaOH
* Y grams of CuCl₂
* Calculate moles of NaOH:
* Moles of NaOH = (mass of NaOH / molar mass of NaOH)
* Molar mass of NaOH = 40 g/mol
* Calculate moles of CuCl₂:
* Moles of CuCl₂ = (mass of CuCl₂ / molar mass of CuCl₂)
* Molar mass of CuCl₂ = 134.45 g/mol
4. Calculate the Mole Ratio:
* The balanced equation tells us the mole ratio of NaOH to CuCl₂ is 2:1. This means for every 2 moles of NaOH, you need 1 mole of CuCl₂ to react completely.
5. Determine the Limiting Reagent:
* Divide the moles of each reactant by its corresponding coefficient in the balanced equation:
* NaOH: (moles of NaOH) / 2
* CuCl₂: (moles of CuCl₂) / 1
* The reactant with the smaller value is the limiting reagent.
Example:
Let's say you have:
* 10 grams of NaOH (0.25 moles)
* 15 grams of CuCl₂ (0.11 moles)
* NaOH: (0.25 moles) / 2 = 0.125
* CuCl₂: (0.11 moles) / 1 = 0.11
In this case, CuCl₂ is the limiting reagent because its value after dividing by the coefficient is smaller.
Key Point:
You need to know the actual masses or concentrations of NaOH and CuCl₂ to determine the limiting reagent in a specific scenario.
