when calculating the molarity of 5% naoh, you are given the solution density of 1.055 g/mL. you also know that 30 ml total of the solution was used during the experiment.
To calculate the molarity of a solution, you need to know the amount of solute (in moles) and the volume of the solution (in liters).
First, convert the given solution density of 1.055 g/mL to grams per liter (g/L).
1.055 g/mL x 1000 mL/L = 1055 g/L
Next, calculate the amount of solute (NaOH) in the solution using the given percentage (5%) and the volume of the solution used (30 mL).
5% NaOH means there are 5 grams of NaOH present in 100 mL of solution.
So, in 30 mL of solution, there will be (5 grams/100 mL) x 30 mL = 1.5 grams of NaOH.
Finally, convert the amount of solute (1.5 grams) to moles using the molar mass of NaOH.
The molar mass of NaOH is: 22.99 g/mol (Na) + 16.00 g/mol (O) + 1.01 g/mol (H) = 39.99 g/mol
1.5 grams / 39.99 g/mol = 0.0375 moles
Now that you have the moles of solute and the volume of solution in liters (30 mL = 0.03 L), you can calculate the molarity.
Molarity (M) = moles of solute / volume of solution in liters
M = 0.0375 moles / 0.03 L = 1.25 M
Therefore, the molarity of the 5% NaOH solution is 1.25 M.