NAOH COLOUR ON PH PAPER
In an experiment to test the pH of a given sample using pH paper, four students recorded the following observations.
Sample taken pH paper colour turned to
(I) Water Green
(II) Dil. HCl Red
(III) Dil. NaOH Blue
(IV) Dil. acetic acid Orange
Which one will have pH value of 7?
What are the colour of pH paper , approximate pH value, nature of substance for the following solutions :-
Saliva (before meal ) , saliva (after meal) , lemon juice, colourless aerated drink , carrot juice , coffee, tomato juice , tap water, 1M NaOH , 1M HCl
A drop of solution 'X' is placed on a strip of pH paper. A deep red colour is produced. The solution 'X' is: