1. An example of water – borne disease is _______.
Answer: d. Typhoid
2. The sedimented and floating materials are removed by this treatment process.
a. primary treatment
b. secondary treatment
c. tertiary treatment
d. peripheral treatment
Answer: a. primary treatment
3. Which is a non – renewable resource?
c. natural gas
d. all the above
Answer: d. All the above
4. _______ is the chief component of natural gas.
Answer: b. methane
1. A true solution is a homogeneous mixture of solute and solvent. Chalk powder in water is a heterogenous mixture. Is it a true solution?
Answer: No , it is a suspension
2. A solution that contains water as the solvent is called an aqueous solution. If carbon di sulphide is a solvent in a given solution, then the solution is called ________.
a. aqueous solution
b. non – aqueous solution
Answer: b. non - aqueous solution
3. The solubility that common salt in 100g water is 36g . If 20g of salt is dissolved in it. How much more is required to attain saturation?
4. If two liquids are mutually soluble, they are called ________ liquids.
Answer: a. miscible
5. When Sunlight passes through the window of a classroom, its path is visible. This is due to ________ of light.
Answer: b. scattering
6. The particles in various forms are visible only under an ultra microscope. A solution containing such particles is called ________.
a. True solution
b. colloidal solution
Answer: b. colloidal solution
7. The number of components in a binary solution are / is ________.
Answer: b. two
8. The mixture of gases used by deep – sea divers is ________.
a. Helium – Oxygen
b. Oxygen - Helium
Answer: a. Helium – Oxygen
9. Soil cannot store more nitrogen than it can hold. Hence soil is said to be in a state of ________.
Answer: a. saturation
10. In an endothermic process, solubility increases with ________ in temperature.
Answer: a. increase
11. Aquatic species are more comfortable in cold water because ________.
a. as the temperature decreases, the solubility of dissolved oxygen increase.
b. as the temperature increases, the solubility of dissolved oxygen increase.
c. as the temperature increases, the solubility of dissolved oxygen decrease.
Answer: As the temperature decrease, the solubility of dissolved oxygen increase.