3
Q:

Dust particles in the air of large industrial cities are removed by 

A) Sedimentation B) Electrophoresis
C) Tyndall effect D) Brownian movement

Answer:   B) Electrophoresis



Explanation:

Dust particles such as coal dust(smoke) are fine particle of a solid (carbon in the case of smoke) dispersed in air. They are colloidal systems and the particles are charged either positive or negative. In an applied electrical field, they are attracted towards the opposite electrodes. Movement of the particles towards the electrodes is known as 'electrophoresis'. Hence electrophoresis is applied to remove smoke within the chimeny itself without allowing it to escape into the air and cause nuisance.

Subject: Chemistry
Q:

The percentage of nitrogen in the air is about

A) 74% B) 76%
C) 78% D) 80%
 
Answer & Explanation Answer: C) 78%

Explanation:
Report Error

View Answer Report Error Discuss

Filed Under: Chemistry
Exam Prep: Bank Exams

3 635
Q:

Methane contributes towards global warming so it is called a _________________ gas.

 

A) poisonous B) carcinogenic
C) infectious D) greenhouse
 
Answer & Explanation Answer: D) greenhouse

Explanation:
Report Error

View Answer Report Error Discuss

Filed Under: Chemistry
Exam Prep: Bank Exams

2 5257
Q:

Which of the following is a metal?

 

A) Sulphur B) Nitrogen
C) Oxygen D) No option is correct
 
Answer & Explanation Answer: D) No option is correct

Explanation:
Report Error

View Answer Report Error Discuss

Filed Under: Chemistry
Exam Prep: Bank Exams

1 2953
Q:

Which of the following group is NOT Dobereiner Triads?

 

A) Li, Na, K B) N, P Au
C) Cl, Br, I D) Ca, Sr, Ba
 
Answer & Explanation Answer: B) N, P Au

Explanation:
Report Error

View Answer Report Error Discuss

Filed Under: Chemistry
Exam Prep: Bank Exams

2 10699
Q:

Safety matches contain

A) Sulphur B) Phosphorus
C) Magnesium D) Potassium
 
Answer & Explanation Answer: B) Phosphorus

Explanation:
Report Error

View Answer Report Error Discuss

Filed Under: Chemistry
Exam Prep: AIEEE , Bank Exams

2 575
Q:

Air ___________________ are the substances which contaminate the air.

A) Reactants B) Irritants
C) Resistants D) Pollutants
 
Answer & Explanation Answer: D) Pollutants

Explanation:
Report Error

View Answer Report Error Discuss

Filed Under: Chemistry
Exam Prep: Bank Exams

2 567
Q:

By using which foam the Researchers from Indian Institute of Technology – Bombay have made a low cost piezo resistive vibration sensor?

A) Only Polyurethane B) Only Polyethylene
C) Both Polyurethane and Polyethylene D) Neither Poly urethane nor Polyethylene
 
Answer & Explanation Answer: B) Only Polyethylene

Explanation:
Report Error

View Answer Report Error Discuss

Filed Under: Chemistry
Exam Prep: Bank Exams

4 632
Q:

Which of the following is NOT a compound?

 

A) Ammonia B) Milk
C) Sodiumchloride D) Chalk
 
Answer & Explanation Answer: B) Milk

Explanation:
Report Error

View Answer Report Error Discuss

Filed Under: Chemistry
Exam Prep: Bank Exams

5 9274