Civil Engineering - UPSC Civil Service Exam Questions - Discussion

42. 

A sample of ground water at a pH of 7.0 contains 122 mg/l of bicarbonates. What is the alkalinity of this water (in terms of CaC0 ) ?

[A]. 120 mg/1
[B]. 60 mg/1
[C]. 100 mg/1
[D]. 200 mg/l

Answer: Option C

Explanation:

No answer description available for this question.

Vikram Syal said: (Mar 5, 2018)  
bicarbonate means hco3 negative, equivalent wt of HCO3 IS 2.

No of gram equivalent = given wt./equivalent wt of ca2co3 50.

Given wt.= 2*50 = 100.

Mudassir said: (Apr 28, 2019)  
Equivalent of hco3 is 1.
So, 1*50 will be 50.

Mohammad Rizwan said: (Nov 19, 2019)  
Alkalinity, in this case, can be calculated as,
amount of sample in mg/L * (Equivalent wt of CaCo3/Equivalent wt of ion).

Here,
Amount of Sample = 122mg/L.
Equivalent wt of CaCO3 = 50.
Equivalent wt of HCO3-- = 61.

Therefore : 122*(50/61)=100mg/L as CaCO3.

Also,
Eq wt can be calculated as,
Eq Wt= Molecular Wt/Valancy.
Eq wt of CaCO3 = 100/2.
Wq wt of HCO3- = 61/1.
Molecular wt of HCO3-= (1+12+(16*3)) = 61.

Post your comments here:

Name *:

Email   : (optional)

» Your comments will be displayed only after manual approval.