Page 236 - Chemistry ICSE Class IX

224 ICSE Chemistry – 9

Procedure
Follow the steps given below:

y Take two test tubes. Label them as A and B.
y Take about 5 mL of UCORNG # KP VGUV VWDG # and 5 mL of UCORNG $ KP VGUV VWDG $.
y Add 1 mL soap solution in each of the test tubes and shake vigorously.
y Record your observations.

Observations

y The sample A (in test tube A) does not give lather and forms curdy precipitate.
y The sample B (in test tube B) gives good lather easily with soap solution.
(Note: Please write your observations. These observations are given to illustrate.)

Conclusion
From the observations made above:

y Sample A is hard water, and
y Sample B is soft water.

EXPERIMENT 6.2

Objective

6Q FKHHGTGPVKCVG DGVYGGP VGORQTCT[ CPF RGTOCPGPV JCTF YCVGT

Apparatus Required
Test tubes (2), Beakers (2), Burner, Tripod stand

Materials Required

Two samples of water labelled as A and B - one of the samples is of temporary hard water, whereas the other
one is of permanent hard water.

Procedure

Perform the experiment through the following steps:

y Test both the samples of water with soap solutions and note down your observations.
y Take two beakers, and label them as A and B.
y Pour about 20 mL of sample A (temporary hard water) in beaker A and 20 mL of sample B (permanent
hard water) in beaker B.

y Boil both the samples on low flame for about 2-3 min, and keep them aside for cooling.
y Filter both the solutions separately.
y Take about 5 mL of each sample in separate test tubes and add 1 mL of soap solution in each. Shake
the solutions vigorously.
y Note down your observations.