In three test tubes A, B and C, three different liquids namely, distilled water, underground water and distilled water in which a pinch of calcium sulphate is dissolved, respectively are taken. Equal amount of soap solution is added to each test tube and the contents are shaken. In which test tube will the length of the foam (lather) be longest? Justify your answer.
In three test tubes A, B and C, three different liquids namely, distilled water, underground water and distilled water in which a pinch of calcium sulphate is dissolved, respectively are taken. Equal amount of soap solution is added to each test tube and the contents are shaken. In which test tube will the length of the foam (lather) be longest? Justify your answer.
The length of the foam (lather) will be longest in test tube C. This is because the soap solution in test tube C contains a pinch of calcium sulphate, which is a soap-like substance that helps to create a rich lather.
Marking Scheme
- 1/1
- 2/1
Hint
Recall the properties of soap solution.
Quick Oral Answer
The length of the foam (lather) will be longest in test tube C because the soap solution in test tube C contains a pinch of calcium sulphate, which is a soap-like substance that helps to create a rich lather.
Analysis & Explanation
The length of the foam (lather) will be longest in test tube C because the soap solution in test tube C contains a pinch of calcium sulphate, which is a soap-like substance that helps to create a rich lather.
Common Mistakes
- 1Forgetting to consider the effect of adding a pinch of calcium sulphate.
- 2Incorrectly comparing the length of the foam (lather) in each test tube.
Interesting Facts
Soap solution is a mixture of soap and water.
Calcium sulphate is a soap-like substance that helps to create a rich lather.
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Frequently Asked Questions
How many marks does this question carry in CBSE Class 10 Science 2019?
This question carries 2 marks in the CBSE Class 10 Science 2019 examination.
Which chapter does this question come from in Science?
This question is from the chapter "Carbon and its Compounds" in the CBSE Class 10 Science syllabus.
What topic does this question cover in Science?
This question covers the topic "Soap Solution" from CBSE Class 10 Science.
What type of question is this in the CBSE Class 10 Science 2019 paper?
This is a Short Answer question from Section E in the CBSE Class 10 Science 2019 paper.