Consider the following statements : 1. Soap cannot be used in acidic water. 2. Ionic part of a soap is COO~.Na+. 3. Soap dissolves in water faster than detergent. Which of the statements given above is/are correct?

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Q: 90 (NDA-II/2009)
Consider the following statements :
1. Soap cannot be used in acidic water.
2. Ionic part of a soap is —COO~.Na+.
3. Soap dissolves in water faster than detergent.
Which of the statements given above is/are correct?

question_subject: 

Science

question_exam: 

NDA-II

stats: 

0,6,6,6,3,2,1

keywords: 

{'soap dissolves': [0, 0, 1, 0], 'acidic water': [0, 0, 1, 0], 'soap': [0, 0, 0, 3], 'detergent': [0, 0, 0, 1], 'ionic part': [0, 0, 1, 0]}

The correct answer is option 1 - 1 and 2 are correct statements.

Let`s dissect each statement to better understand why they are correct or incorrect:

Statement 1: "Soap cannot be used in acidic water."

This statement is correct. Soap is made of fatty acids, and in acidic water, the fatty acids in soap will react with the acid to form a precipitate. This will reduce the ability of soap to lather and clean effectively.

Statement 2: "Ionic part of a soap is —COO~.Na+."

This statement is correct. Soap molecules have a polar head and a nonpolar tail. The ionic part of a soap molecule is the sodium ion (Na+), which is attracted to water (polar). The carboxylate ion (-COO~) is the ionic part that is attracted to oil and grease (nonpolar). The combination of these two parts allows soap to effectively remove dirt and grease from surfaces.

Statement 3: "Soap dissolves in water faster than detergent."

This statement is incorrect. Detergents are specifically designed to dissolve in water more easily than soap. Unlike soap, detergents do not react with hard water (water with high mineral content) and can