NDA 2026
- Exam
- NDA
- Year
- 2026
- Subject
- General Ability
- Chapter
- General Science
NDA 2026 · General Ability · General Science
Consider the following statements: I. Pine oil is used as...
Consider the following statements:
I. Pine oil is used as antifoaming agent in the emulsion paints.
II. Protective colloids are used in the emulsion paints to decrease their stability.
III. Driers having oxidizable oils are added to the emulsion paints to accelerate drying process.
Which of the statements given above is/are correct?
I. Pine oil is used as antifoaming agent in the emulsion paints.
II. Protective colloids are used in the emulsion paints to decrease their stability.
III. Driers having oxidizable oils are added to the emulsion paints to accelerate drying process.
Which of the statements given above is/are correct?
Options
- AI and II
- BI only
- CII and III
- DI and III
Correct answer
B. I only
Step-by-step solution
Statement I is correct. Pine oil is used as an antifoaming agent in emulsion paints to prevent the formation of foam during the manufacturing and application processes.
Statement II is incorrect. Protective colloids (such as polyvinyl alcohol or casein) are added to emulsion paints to increase their stability, not decrease it. They prevent the dispersed polymer particles from coagulating.
Statement III is incorrect. Emulsion paints are water-based and dry primarily through the evaporation of water followed by the coalescence of polymer particles. Driers containing oxidizable oils (drying oils) are typically added to oil-based paints to accelerate the drying process via oxidation and cross-linking, not to emulsion paints.
Therefore, only Statement I is correct.
Statement II is incorrect. Protective colloids (such as polyvinyl alcohol or casein) are added to emulsion paints to increase their stability, not decrease it. They prevent the dispersed polymer particles from coagulating.
Statement III is incorrect. Emulsion paints are water-based and dry primarily through the evaporation of water followed by the coalescence of polymer particles. Driers containing oxidizable oils (drying oils) are typically added to oil-based paints to accelerate the drying process via oxidation and cross-linking, not to emulsion paints.
Therefore, only Statement I is correct.