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Question
Using given sample of temporary and permanent hard water, soft water, ordinary soap, detergent and washing soda how would you remove temporary hardness from water without using a chemical compound?
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Solution
Temporary hardness can be removed by heating the hard water.
Experiment
Temporary hard water softened by heating
- Temporary hard water is taken in a beaker and heated
- After the gases escape out, the water is filtered through a filter paper.
- Ordinary soap is rubbed – inside the filtered solution.
Observation
- The boiled and filtered sample of – temporary hard water lathers readily with soap.
Result
- Temporary hard water can be – softened by heating.
\[\ce{\underset{\text{[in temporary hard water]}}{Ca(HCO3)2} ->\underset{\text{[ppt. filtered out]}}{CaCO3↓} +\underset{\text{[filtered water is soft]}}{CO2 + H2O}}\]
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