Why is phenolphthalein used as an indicator? In basic solution,the acidic proton in the phenolphthalein will be captured by the hydroxide ions and forms a quinoid structure which is pink in colour. So, this appearance of pink colour will help to identify the end point of this titration. ...
Suppose you chose phenolphthalein, which changes color at the end point from colorless (acidic) to pink at pH 8.5 The Ka of hydrocyanic acid, HCN, is 5.0 x 10-10. What is the pH of 0.050 M HCN(aq)? A certain indicator, HIn, has Ka = 1.0 ...
In industry, acid-base neutralization is used in waste treatment to neutralize acidic or basic wastewaters. In laboratory experiments, acid-base neutralization reactions can be observed through various indicators. For instance, phenolphthalein is a common indicator that turns pink in basic solutions and...
In acidic solutions, phenolphthalein is colorless but in basic solutions, it is bright pink. When carrying out a titration, phenolphthalein is used... See full answer below.Become a member and unlock all Study Answers Start today. Try it now Create an account Ask a question Our experts ...
Which of the following is weak acid indicator? Phenolphthaleinis a colourless, weak acid which dissociates in water forming pink anions. Under acidic conditions, the equilibrium is to the left,and the concentration of the anions is too low for the pink colour to be observed. ...
Benzene methanoic acyl group: Take about 1g of this product, accurately weigh it, add 50ml of acetone-ethanol-water (2:2:1) to dissolve it, add phenolphthalein as the indicator, and titrate with sodium hydroxide titration solution (0.1mol/L). Correct the titration result with a blank test...
Q. Assertion (A): in the titration of Na2CO3 with HCl using methyl orange indicator, the volume required at the equivalence point is twice that of the acid requried using phenolphthalein indicator. Reason (R): Two moles of HCl is requried for the complete neutralisation of 1 " mol of "...
pH at which an acidic indicator withKin=1×10−5changes colour when the indicator is1×10−3M is View Solution Free Ncert Solutions English Medium NCERT Solutions NCERT Solutions for Class 12 English Medium NCERT Solutions for Class 11 English Medium ...
A pH meter uses probes to measure the electrical conductivity of a solution Indicators change colour at different pH values, so different indicators are used to identify different pH values bromothymol blue for pH 6 – 7.6 phenolphthalein for pH 8.2 – 10 many natural sources (ie...
. This can be proven. Add phenolphthalein indicator to distilled water. Let's presume the pH was 7 or just slightly below. the indicator should be a slight pink color. If you simply exhale over an erlenmeyer flask and swirl the water, the indicator will go clear after a matter of ...