NaOH + HCl -> NaCl + H2O
What is the molarity of a NaOH solution that required 31.6mL to neutralize 25.0mL of a 0.145 M HCl solution?
mols HCl = M x L = ?
mols NaOH = mols HCl(look at the coefficients in the balanced equation.
M NaOH = mols NaOH/L NaOH. You know L and you know mols, solve for M NaOH.
To determine the molarity of the NaOH solution, we can use the concept of stoichiometry and the equation balanced equation you provided:
NaOH + HCl -> NaCl + H2O
From the balanced equation, we can see that the mole ratio between NaOH and HCl is 1:1. This means that one mole of NaOH will react with one mole of HCl.
First, let's calculate the number of moles of HCl in 25.0 mL of a 0.145 M HCl solution:
Molarity (M) = moles/volume (in L)
Rearranging the formula to solve for moles:
moles = Molarity × volume (in L)
moles of HCl = 0.145 M × (25.0 mL / 1000 mL/1 L) = 0.003625 moles
Since the reaction is 1:1, this means that the number of moles of NaOH required to neutralize the HCl is also 0.003625 moles.
Now we can calculate the molarity of the NaOH solution using the volume and number of moles:
Molarity = moles/volume (in L)
Molarity = 0.003625 moles / (31.6 mL / 1000 mL/1 L) = 0.1145 M
Therefore, the molarity of the NaOH solution is 0.1145 M.
To find the molarity of the NaOH solution, you can use the concept of stoichiometry and the equation of the reaction between NaOH and HCl. Here's how you can calculate it:
Step 1: Write and balance the equation for the reaction:
NaOH + HCl -> NaCl + H₂O
Step 2: Determine the stoichiometry of the reaction:
From the balanced equation, you can see that one mole of NaOH reacts with one mole of HCl to form one mole of NaCl and one mole of H₂O.
Step 3: Calculate the number of moles of HCl in the given volume:
Using the equation Molarity (M) = Moles (mol) / Volume (L), we can rearrange it to Moles (mol) = Molarity (M) × Volume (L). Therefore, the moles of HCl can be calculated as:
Moles of HCl = Molarity of HCl × Volume of HCl solution
Moles of HCl = 0.145 M × 0.025 L = 0.003625 mol
Step 4: Since the stoichiometry of HCl and NaOH is 1:1, the moles of NaOH required to neutralize the given moles of HCl is also 0.003625 mol.
Step 5: Calculate the molarity of NaOH solution:
Molarity of NaOH = Moles of NaOH / Volume of NaOH solution
We need to find the volume of the NaOH solution that contains 0.003625 moles. The volume can be calculated using the equation:
Volume of NaOH solution = Moles of NaOH / Molarity of NaOH
We are given that the volume of NaOH solution is 31.6 mL, which is equal to 0.0316 L. So we can calculate the molarity of NaOH as:
Molarity of NaOH = 0.003625 mol / 0.0316 L ≈ 0.115 M
Therefore, the molarity of the NaOH solution is approximately 0.115 M.