Discussion
Consider the following statements about moisture in a drying solid:
1. Free moisture is that above the equilibrium value.
2. Bound moisture exerts a vapour pressure below that of pure water.
3. Critical moisture is a fixed property of the material.
Which of the statements given above is or are correct?
Answer: A
Correct answer: 1 and 2 only
Statement 1 is correct: free moisture is the moisture above the equilibrium value, the removable fraction. Statement 2 is correct: bound moisture is held chemically or in fine capillaries and cell walls, so it exerts a vapour pressure below that of pure water and is correspondingly harder to remove.
Statement 3 is false. Critical moisture is not a fixed property of the material - it depends on how hard the drying is and on the thickness of the piece. Drying faster raises it, because the surface dries out sooner relative to the supply of moisture from within.
Post your comment
Please log in or register to post a comment.
Examination Categories
- SSC Exams
- Banking Exams
- Teaching Exams
- Civil Services Exams
- Railways Exams
- Engineering Recruitment Exams
- Defence Exams
- State Government Exams
- Police Exams
- Insurance Exams
- Nursing Exams
- Other Government Exams
- NRA CET
- PG Entrance Exams
- Campus Placement
- MBA Entrance Exams
- CUET and UG Entrance
- Judiciary Exams
- Regulatory Body Exams
- Software Development