WorksheetsAcid–base titrations (Acidimetry and Alkalimetry)
Total questions: 20
Worksheet time: 10mins
Describe in detail acid–base titrations by selecting all statements that correctly summarize their key features, reagents, and defining reaction.
They involve a neutralization process between an acid and a base forming salt and water.
The characteristic reaction for these titrations is H++OH−→H2O .
In this context, an acid is defined as a substance that, when dissolved in water, gives OH− ions.
A base is a substance that, when dissolved in water, gives OH− ions.
Commonly used reagents include acids such as HCl and H2SO4 and bases such as NaOH, KOH, and sodium bicarbonate.
In the assay of sodium bicarbonate, which titration method is used?
Acidimetric method
Alkalimetric method
Argentimetric method
Complexometric method
What is the chemical formula of sodium bicarbonate used in the direct titration method of its assay?
NaHCO3
Na2CO3
Na2HPO4
NaCl
Which statements form the stated principle of the sodium bicarbonate assay?
Sodium bicarbonate is titrated by an acidimetric method
Sodium bicarbonate, a salt of strong base NaOH and carbonic acid, is dissolved in water
The alkaline solution is directly titrated with strong acids like HCl using methyl orange
The assay requires argentometric precipitation with silver nitrate
For preparing 1 M hydrochloric acid for the assay, what volume of commercial concentrated HCl is diluted to make 100 ml?
8.9 ml
1.5 ml
0.1 ml
27.0 ml
In preparing 1 M HCl, to what final volume is the solution made up with distilled water?
100 ml
250 ml
500 ml
50 ml
At approximately what temperature is anhydrous sodium carbonate previously heated for 1 hour before use in standardization?
270∘C
100∘C
150∘C
350∘C
For standardizing HCl in this procedure, what volume of water is used to dissolve the weighed sodium carbonate in a 250 ml conical flask?
100 ml
50 ml
150 ml
200 ml
Which indicator and amount are added during the standardization of hydrochloric acid in this assay?
0.1 ml of methyl red solution
3 drops of phenolphthalein solution
0.5 ml of methyl orange solution
1.0 ml of bromothymol blue solution
Assay of boric acid/boracic acid is performed by which titrimetric method?
Acid–base alkalimetric direct titration of boric acid dissolved in a glycerin–water mixture using phenolphthalein and standardized NaOH
Redox titration with potassium permanganate in acidic medium using a self-indicator
Non-aqueous titration with perchloric acid in glacial acetic acid using crystal violet
Argentometric titration of borate with silver nitrate using potassium chromate
According to the described assay of ammoniated mercury, which type of titration is used?
Acid–base titration (indirect titration)
Redox titration
Complexometric titration
Non-aqueous titration
In the worksheet section on the assay of ammoniated mercury, what is the chemical formula stated for ammoniated mercury?
NH2HgCl
NH4HgCl
HgNH2Cl2
NH2HgBr
In the principle of the assay, the sample is dissolved in a solution of which reagent before further treatment?
Potassium iodide
Sodium chloride
Potassium bromide
Ammonium nitrate
During the assay, the precipitate of HgCl2 dissolves in excess potassium iodide with liberation of equivalent alkalies. Which alkalies are titrated against standard acid using methyl orange as indicator?
Ammonia and KOH
NaOH and NH4OH
K2CO3 and NH3
Ca(OH)2 and NH3
Which titrant and indicator are specified for titrating the liberated alkali in the assay of ammoniated mercury?
0.1 N HCl using methyl orange
0.1 N NaOH using phenolphthalein
0.05 N H2SO4 using methyl red
0.1 N HCl using phenolphthalein
According to the listed reactions, what soluble product forms when HgCl2 reacts with 2 KI during the assay?
K2HgI4
HgI2
K2HgCl4
KI3
Which category is assigned to ammoniated mercury in the worksheet?
Topical antiseptic and disinfectant
Systemic antibiotic
Analgesic and antipyretic
Topical corticosteroid
Which listed use is given for ammoniated mercury in the worksheet?
In treatment of psoriasis
Management of hypertension
Oral contraceptive
Treatment of diabetes mellitus
Which additional use is stated for ammoniated mercury?
To treat minor skin infections and other skin disorders
To relieve migraine headaches
To treat asthma exacerbations
To manage cardiac arrhythmias
Assay of Ammonium Chloride (I.P. 1985): Select all statements that correctly describe the method and standard as presented in the note on the assay of ammonium chloride.
It is an acid–base titration performed by an indirect titration method.
A weighed quantity of ammonium chloride is dissolved in water and treated with neutralised formaldehyde.
The liberated HCl is titrated with standard sodium hydroxide using phenolphthalein to a pink end point.
The assay uses 0.1 N sulfuric acid with methyl orange as the indicator.
The I.P. standard requires not less than 99% and not more than 100.5% of NH4Cl.
