When KHP is added to NaOH what color changes?

Phenolphthalein is colorless in acidic solution, but turns red in basic solution. When one drop more NaOH is added than is required to react with the KHP in a sample, the sample becomes basic and the indicator changes color.

What is KHP to NaOH?

A commonly used primary standard for titration with sodium hydroxide solution is the weak acid potassium hydrogen phthalate or KHP (C8H5O4K). In this reaction as well, one mole of KHP completely reacts with one mole of NaOH. The titration of NaOH with KHP involves adding NaOH from the burette to a known volume of KHP.

How do you find the moles of NaOH in a titration with KHP?

1. The number of moles of KHP is found by dividing the mass of KHP by the molecular weight of KHP. 2. The number of moles of NaOH is found by multiplying the moles of KHP by the mole ratio of NaOH to KHP given by the above, balanced chemical reaction.

What does a Gran plot tell you?

A Gran plot (also known as Gran titration or the Gran method) is a common means of standardizing a titrate or titrant by estimating the equivalence volume or end point in a strong acid-strong base titration or in a potentiometric titration.

What is Gran alkalinity?

Gran alkalinity method is a more accurate technique used explicitly for low level alkalinity samples. It is performed on samples with a pH less than 7.0. Method Summary. The alkalinity titration is carried well past the total inflection point to about pH 3.0.

Why is phenolphthalein a good indicator for titrating KHP with NaOH?

A strong acid- strong base titration is performed using a phenolphthalein indicator. Phenolphtalein is chosen because it changes color in a pH range between 8.3 – 10. It will appear pink in basic solutions and clear in acidic solutions.

Why is phenolphthalein a useful indicator for titrating KHP and NaOH?

I always used to like phenolphthalein inasmuch as its acidic form is COLOURLESS, and its endpoint is very recognizable from either direction. Phenolphthalein is usually used since it is easy to detect visually a slight pink color from a colorless liquid solution.

Why is NaOH standardized with KHP?

NaOH is hygroscopic, so it is not possible to weigh it accurately. KHP is hygroscopic, so it is not possible to weigh it accurately. NaOH is a primary standard, so a solution of it needs to be standardized. NaOH is hygroscopic, so it is not possible to weigh it accurately.

Why is phenolphthalein the best indicator for the titration of KHP with NaOH?

How does a potentiometric titration work?

Potentiometric titration belongs to chemical methods of analysis in which the endpoint of the titration is monitored with an indicator electrode that records the change of the potential as a function of the amount (usually the volume) of the added titrant of exactly known concentration.

How does titration determine alkalinity?

The total alkalinity analysis involves titration. In this test, titration is the addition of small, precise quantities of sulfuric acid (the reagent) to the sample until the sample reaches a certain pH (known as an endpoint). Th e amount of acid used corresponds to the total alkalinity of the sample.

What happens when NaOH is added to KHP solution?

The resultant Acidic solution was transparent, with a small amount of undissolved granules of KHP. As the transparent NaOH solution came into contact with transparent phenolphthalein in the KHP solution, it turned pink which on shaking became transparent.

How do you calculate the number of moles of KHP in NaOH?

Number of moles of KHP in 2.00 grams = (m/M) = (2/204.22) mol = 0.00979 mol [c] KHP = n/V = (0.00979/0.1) mol dm -3 Number of moles of KHP in 0.01 dm 3 of solution in conical flask = [c] x V = 0.0979 x 0.01 = 9.79 x 10 -4 mol. From mole ratio, number of moles of NaOH = 0.00979 mol.

What was the reason for the flaw in the KHP experiment?

This flaw was due to allowing excess sodium hydroxide to flow, causing the KHP solution to become pinker than it should have. This might have caused some deviations because the volume of sodium hydroxide added was excess. The theoretical value of NaOH to be poured was 9.50 cm 3, and more or less than 0.1 cm 3…

How do you standardize sodium hydroxide (NaOH) solution?

To standardize a sodium hydroxide (NaOH) solution against a primary standard acid [Potassium Hydrogen Phthalate (KHP)] using phenolphthalein as indicator. Need help with your writing assignment? Get online help from vetted experts in any field of study. Two 100 cm 3 Beakers (One for making the KHP solution, one for pouring NaOH into the burette)