Phenolphthalein indicator pH range is?

Aqueous solution of orthoboric acid can be titrated against sodium hydroxide using phenolphthalein indicator only in presence of

(a) Define a universal indicator . Mention its one use. (b) Solution A gives pink colour when a drop of phenolphthalein indicator is added to it. Solution B gives red colour when a drop of methyl orange is added to it. What type of solutions are A and B which one of the solutions A and B will have a higher pH value ? (c) Name one salt whose solutions has pH more than 7 and one salt whose solution has pH less than 7.

In the mixture of (NaHCO_3 + Na_2CO_3) , volume of HCI required is x mL with phenolphthalein indicator and y mL with methly orange indicator in the same titration. Hence, volume of HCI for complete reaction of Na_2CO_3 is : (a) 2x (b) y (c) x/2 (d) (y-x)

A bottle, which contains 200 ml of 0.1 M KOH, absorbs 1 millimole of CO_(2) from the air. If the solution is then treated with standard acid using phenolphthalein indicator, the normality of solution formed by absorption of CO_(2) is :

Boric acid can be titrated against sodium hydroxide using phenolphthalein as an indicator only in the presence of polyhydroxy compounds like glycol. Glycerol etc. Give reason.

A sample of NaHCO_(3) + Na_(2)CO_(3) required 20 ml of HCl using phenolphthalein as indicator and 35ml more required if methyl orange is used as indicator . Then molar ratio of NaHCO_(3) to Na_(2)CO_(3) is

If amixture of Na_(2)CO_(3) and NaOH in equimolar quantities when reacts with 0.1 M HCl in presence of phenolphthalein indicator consumes 30 ml of the acid. What will be the volume (in mL) of 0.15 M H_(2)SO_(4) used in the separate titration of same mixture in presence of methyl orange indicator.

A mixutre solution of KOH and Na_2CO_3 requires 15 " mL of " (N)/(20) HCl when titrated with phenolphthalein as indicator.But the same amoound of the solutions when titrated with methyl orange as indicator requires 25 " mL of " the same acid. Calculate the amount of KOH present in the solution.

One gram of a mixture of NaHC_2O_4 and Na_2C_2O_4 dissolved in water consumes in titration 50.28 " mL of " 0.1 N NaOH with phenolphthalein as indicator. If 1 g of the mixture is heated to constant weight, what would be the weight of Na_2CO_3 produced?