The titration data are as following. Answer. Why can’t an exact solution of NaOH be prepared? NaOH does not make a good standard solution because the NaOH when you weigh it out absorbs moisture from the air. What would happen if the buret was washed and rinsed property but not conditioned with sodium hydroxide solution, prior to standardizing the sodium hydroxide solution? An alternative approach is to buy small quantities of standard solutions (ready-made or concentrated) and use these to standardise one’s own solutions. chemistry. What is the complete formula of the primary standard that will he used to standardize the NaOH in this experiment? Molarity . Substances whose standard solutions cannot be prepared directly are called secondary standards. Find the unknown concentrations. Top Answer. A primary standard substance can be weighed accurately because it is stable (does not decompose) and not hygroscopic (does not absorb moisture from the atmosphere). why NaOH must be standardized? And I had learned it's answer the hard way since I had to work with NaOH crystals during my 12th grade chemistry investigatory project. Why does a solution of NaOH have to be standardized against a primary standard as supposed to just using the mass and volume to calculate the concentration - 13601698 This is a question that my chemistry professor presented to our class on our first week at college. This is why they never introduce standardization in general chemistry courses, I only got to grips with it when I took up Analytical Chemistry, and back then it was really tedious to do. You use 37.0mL of NaOH to titrate 100mL of HCl and 13.6 mL of NaOH to titrate 50.0mL of 0.0782 M H2SO4. SUITABLE CHEMICALS FOR STANDARD SOLUTIONS. Why should the standardized NaOH solution be kept in a stoppered bottle? 0 1 2. KHP is a monoprotic acid with a molar mass of 204.22 g/mol. … For example, KMn04, NaOH, KOH, etc. The solution you end up with has a concentration that is probably +/-1%. For example, I actually experienced this before where we had to prepare a 1M stock of NaOH, but after standardization it turned out to be around 0.8 (maybe due to the humidity in the lab at the time). Wiki User Answered . 4 0. That is too great a difference, so you must standardize the NaOH against some acid that you can be more exact about, probably +/-0.01% or better. as soon as we open the bottle it absorbs moisture & CO2 out of the air. Why must NaOH be standardized? Asked by Wiki User. 2011-03-09 19:52:26 2011-03-09 19:52:26. because NaOH hasn't a known purity. Why is it necessary to standardize the NaOH solution prior to titrating an unknown acid solution? ... You are given solutions of HCl and NaOH and must determine their concentrations. but also because the CO2 & H2O combine to make carbonic acid which destroys some of the NaOH . its grams become less concentrated in NaOH not only because of the excess weight it absorbs.