How to Determine purity of sodium hydroxide (NaOH, caustic soda)?

by this test you can find purity of sodium hydroxide

This test can be performed by performing a titration test as follows:

Items needed:

–    Calibrated pipette

–    Phenolphthalein reagent as an identifier

–    Erlenmeyer

–    Metal holder base

–    Sodium hydroxide (flake)

–    Hydrochloric acid (HCL) with a molarity of 0.1

First, dissolve 5 gram of flake soda in one liter of water and place 10 ml of this solution in a Erlenmeyer pipette. Make hydrochloric acid M 0.1 with the help of one liter of water and transfer it to the burette until it reaches zero point. Then transfer two to three drops of phenolphthalein reagent to Erlenmeyer and sodium hydroxide solution and shake several times.

HC1 + NaOH → NAC1 + H2O

Next, we obtain the net amount of NaOH by the following formulas and divide it by the total amount to obtain the percentage of purity.

Obtain Mole Burt (HCL)

Concentration (HCL) (M0.1 × Volume of registered titrant of burette = mole of HCL in burette

Obtain moles of NaOH within Erlenmeyer

Due to the 1: 1 ratio of these substances in the reaction equation, the concentration of NaOH is equal to the concentration of HCL (M0.1)

Obtaining NaOH concentration in Erlenmeyer