most important questions for class 9

  1. How will you separate a mixture of common salt, sulphur powder and sand?
  2. Is air a mixture or compound? Give reason.
  3. Compare the properties of a true solution, a suspension and a colloidal solution.
  4. Give one reason that support water is a compound not a mixture.
  5. Is all mixtures are homogenous?
  6. What is the particle size of a colloidal solution?
  7. Give an example of non-aqueous solution.
  8. What is mother liquor?
  9. What is Tyndall effect? Explain with example.
  10. What is Brownian motion? In which type of solution Brownian motion occurs.
  11. How does the temperature and pressure affect the solubility of solid and gases in water?
  12. Is hydrochloric acid is a mixture.
  13. Blood and sea water are:-  (a) both mixtures  (b) both are compound (c) blood is a mixture whereas sea water is a compound (d) blood is a compound and sea water is a mixture
  14. Sol and Gel are examples of examples of(a) Solid-solid colloids (b) Sol is a solid-liquid colloid and Gel is liquid solid colloid (c) Sol is a solid-solid colloid and Gel is a solid-liquid colloid (d) Sol is a liquid-solid colloid and Gel is a solid-liquid colloid
  15. In a water-sugar solution:-(1) Water is solute and sugar is solvent   (2) water is solvent and sugar is solute(3) water is solute and water is also solute  (4) none of these
  16. Boron and carbon:- (a) are metalloids (b) boron is metalloid and carbon is non-metal (c) boron is metallic and carbon is a metal (d) boron is non-metal and carbon is a metalloid
  17. What is tyndall effect? Which kinds of solution show it?
  18. Differentiate between homogeneous and heterogeneous mixture?
  19. What is centrifugation? Where it is used?
  20. What is a suspension? What are the properties of suspension?