Use app×
Join Bloom Tuition
One on One Online Tuition
JEE MAIN 2025 Foundation Course
NEET 2025 Foundation Course
CLASS 12 FOUNDATION COURSE
CLASS 10 FOUNDATION COURSE
CLASS 9 FOUNDATION COURSE
CLASS 8 FOUNDATION COURSE
0 votes
46 views
in Chemistry by (62.9k points)
closed by
Which of the following ions will cause hardness in water sample?
A. `Ca^(2+)`
B. `Na^(+)`
C. `Cl^(-)`
D. `K^(+)`

1 Answer

0 votes
by (66.0k points)
selected by
 
Best answer
Correct Answer - A
Bicarbonate, chlorides and sulphates of Ca and Mg are responsible for the hardness of water.
Note: Hard water forms scum/precipiate with soap. Soap canatining out Ca/Mg stearate.
`(C_(17)H_(35)COONa)` reacts with hard water to precipiate out ca/Mg stearate.
` 2C_(17)H_(35)COONa(aq) + M^(2+)(aq) to (C_(17)H_(35)COO)_(2) M darr + 2Na^(+)(aq) ("where", M = Ca//Mg)`

Welcome to Sarthaks eConnect: A unique platform where students can interact with teachers/experts/students to get solutions to their queries. Students (upto class 10+2) preparing for All Government Exams, CBSE Board Exam, ICSE Board Exam, State Board Exam, JEE (Mains+Advance) and NEET can ask questions from any subject and get quick answers by subject teachers/ experts/mentors/students.

Categories

...