Preparation of nano

R. What is the size range of nano particles?

• A. 1-100 nm
• B. 100-500 nm
• C. 500-1000 nm
• D. 1-1000 nm

R. What is the most common method for the preparation of nano particles?

• A. Chemical synthesis
• B. Mechanical milling
• C. Spray drying
• D. Sol-gel method

R. Which of the following is not a physical method for preparing nano particles?

• A. Laser ablation
• B. Chemical reduction
• C. Sol-gel method
• D. Ball milling

R. What is the disadvantage of using the sol-gel method for the preparation of nano particles?

• A. High cost
• B. Low purity
• C. Low yield
• D. Long processing time

R. What is the role of a surfactant in the preparation of nano particles by chemical synthesis?

• A. Stabilize the particles
• B. Increase the yield
• C. Change the size of particles
• D. Enhance the purity

R. What type of milling is used for preparing nano particles?

• A. Attrition milling
• B. Ball milling
• C. High energy milling
• D. All of the above

R. What is the advantage of using mechanical milling for preparing nano particles?

• A. High purity
• B. Low cost
• C. Scalability
• D. All of the above

R. What is the disadvantage of using a wet milling technique for preparing nano particles?

• A. High energy consumption
• B. Low yield
• C. Difficult to scale up
• D. All of the above

R. What is the advantage of using a spray drying technique for preparing nano particles?

• A. Scalability
• B. Low cost
• C. High yield
• D. High purity

R. What is the role of reducing agents in chemical reduction method for preparing nano particles?

• A. Reducing the size of particles
• B. Stabilizing the particles
• C. Controlling the shape of particles
• D. Increasing the purity