A sample of water with soap solution was tested. The students observed...
Sodium (Na+) is incapable of making multivalent cations while Magnesium (Mg2+) and Calcium (Ca2+) exist as multivalent cations. Hence the water will lather
Also because soap is sodium or potassium salts of long chain of fatty acids, hence the common salt dissolved in water cannot displace the sodium in the soap molecules.
=>The sample can lather with the use of soap.
A sample of water with soap solution was tested. The students observed...
Observation:
When a spoonful of common salt is added to water and then tested with soap solution, the observation will be that the soap solution does not lather freely or lathers less compared to the previous observation without the addition of salt.
Explanation:
When soap is dissolved in water, it forms soap molecules. These soap molecules have a hydrophilic (water-loving) head and a hydrophobic (water-hating) tail. The hydrophilic head of the soap molecules interacts with water molecules, while the hydrophobic tail tends to repel water. This property of soap allows it to form a lather and mix with water.
Effect of Common Salt:
When common salt (sodium chloride) is added to water, it dissociates into sodium ions (Na+) and chloride ions (Cl-). These ions interact with the soap molecules and disrupt their structure. The sodium ions compete with the soap molecules for the water molecules, while the chloride ions interact with the hydrophobic tails of the soap molecules.
Effect on Soap Solution:
The presence of common salt in water reduces the effectiveness of soap in lathering. This is because the sodium ions form stronger bonds with water molecules compared to the soap molecules. As a result, the soap molecules are less able to interact with the water molecules and form a stable lather.
Conclusion:
Adding common salt to water before testing it with soap solution reduces the lathering ability of the soap solution. The presence of sodium ions from the salt interferes with the soap molecules' ability to interact with water molecules, resulting in a decrease in lather formation.
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