Question

If 150 mL of 1.0 HCI is completely neutralized by 25 mL of NaOH solution, what is the molarity of NaOH?

Answer 1

To determine the molarity of NaOH, we need to use the balanced chemical equation for the neutralization reaction between HCl and NaOH:

HCl + NaOH → NaCl + H2O

From the equation, we know that 1 mole of NaOH reacts with 1 mole of HCl to form 1 mole of NaCl and 1 mole of water. Therefore, the number of moles of NaOH can be calculated from the volume and molarity of HCl and the volume of NaOH used.

First, we need to convert the volume of HCl to moles:

moles of HCl = volume of HCl (in liters) x molarity of HCl

moles of HCl = 150 mL / 1000 mL/L x 1.0 mol/L

moles of HCl = 0.150 mol

Since the balanced equation shows that 1 mole of NaOH reacts with 1 mole of HCl, the number of moles of NaOH can be calculated as:

moles of NaOH = moles of HCl = 0.150 mol

Finally, we can calculate the molarity of NaOH:

molarity of NaOH = moles of NaOH / volume of NaOH (in liters)

molarity of NaOH = 0.150 mol / (25 mL / 1000 mL/L)

molarity of NaOH = 6.0 mol/L

Therefore, the molarity of NaOH is 6.0 mol/L.

Answer 2

The molarity of NaOH in the given solution is 0.00667 M.

Step-by-step explanation:

In a titration, the molarity of the acid can be determined using the stoichiometry of the acid-base reaction. In this case, 150 mL of 1.0 M HCl is neutralized by 25 mL of NaOH solution. The balanced equation for the reaction is: HCl + NaOH -> NaCl + H2O.

From the balanced equation, we can see that 1 mole of HCl reacts with 1 mole of NaOH. Therefore, the moles of NaOH used can be calculated as follows:

Moles of NaOH = (volume of NaOH in liters) * (molarity of NaOH)

Using the given values, we can calculate:

Moles of NaOH = (25 mL / 1000 mL/L) * (Molarity of NaOH)

Since the volume is given in mL, it needs to be converted to liters by dividing by 1000. Now we can substitute the given values into the equation to find the molarity of NaOH:

Moles of NaOH = (25 / 1000) * (1.0 / 150)

Moles of NaOH = 0.0001667

To find the molarity, divide the moles of NaOH by the volume in liters:

Molarity of NaOH = 0.0001667 moles / (25 / 1000) L

Molarity of NaOH = 0.00667 M