SOLVED PAPER 2024 (CDS) (II) (General Knowledge)

Total Questions: 120

11. In which of the following colloids is the dispersing medium a liquid?

Correct Answer: (d) Shaving cream
Solution:Foam and shaving cream are colloids dispersing medium is Liquid.
SolutionDispersing MediumDispersing phase
MistGasLiquid
foamSolidGas
JellySolidLiquid
Shaving CreamLiquidLiquid

The substance distributed as the colloidal particles is called the dispersed phase and the second phase in which the colloidal particles are scattered is called the dispersion medium.

12. The two isotopes of elemental chlorine are

Correct Answer: (d)
Solution:The two isotopes of elemental chlorine are ³⁵C₁₇ and ³⁷C₁₇.

Isotopes of an element is defined as the atoms of an element having same number of protons or electrons but differ in number of neutrons (mass number).

Isotopes of an element have same chemical properties but different physical properties.

13. Which one among the following metals is not stored under oil?

Correct Answer: (b) Rubidium
Solution:Rubidium metal is not stored under oil. Sodium, Potassium and Lithium are very reactive metals. They are kept in kerosene oil to prevent it from coming in contact with oxygen and moisture.

14. Potassium nitrate is not used

Correct Answer: (d) as a preservative of meat products
Solution:Potassium nitrate is used as a fertiliser and in medicine.

It is one of the major constituents of gunpowder.

In processed meats, potassium nitrate reacts with hemoglobin and myoglobin generating a red colour.

15. The surface of the concrete structure of a new construction is covered with straw/gunny bags by wetting. This is done to

Correct Answer: (a) prevent fast evaporation, until hydration has proceeded well
Solution:The surface of the concrete structure of a new construction is covered with straw/gunny bags by wetting this is done to prevent fast evaporation, until hydration has proceeded well.

This helps to give the concrete element not only rapid strength gain but also improved durability.

16. Which one among the following statements for the gases mentioned below is not correct?

Correct Answer: (b) Helium is a commonly used gas in electric bulbs.
Solution:Statement (b) is not correct. Argon is a commonly used to fill incandescent light bulbs.

It increases bulb life by preventing the tungsten filaments from deteriorating too quickly.

17. Match List-I with List-II and select the correct answer using the code given below the Lists.

Correct Answer: (a)
Solution:The correct matching is A-3, B-1, C-2, D-4

Chemical formula of bleaching powder is CaOCl₂ and chemical name is calcium oxychloride.

Bleaching powder is used as a disinfectant which is used for disinfecting water to make potable water.

Chemical formula of baking powder is NaHCO₃ and chemical name is sodium bicarbonate.

Baking soda is used in the manufacture of detergents, soap and paper.

Chemical formula of washing soda is Na₂CO₃. 10 H₂O and chemical name is aqueous sodium carbonate.

Washing soda is used in removing the permanent hardness of the water.

Chemical formula of Plaster of Paris is CaSO₄ ½ H₂O and chemical name 2 is aqueous calcium sulphate.

Plaster of Paris is used in preparing mould statues and artificial decorative items.

18. Which one among the following statements is not true for glass ?

Correct Answer: (c) Crystallinity develops on cooling of the molten mass of the glass.
Solution:Statement (c) is not true for glass. Glass is a homogeneous mixture of silicates of various alkaline metals of non crystallised and transpararent or non-transpararent chemical.

Glass utensils are allowed to cool slowly, steadily and moderately.

19. Which one among the following is responsible for determining the chemical properties of an element?

Correct Answer: (b) Electrons
Solution:Electrons is responsible for determining the chemical properties of an element.

Electrons located in the outermost shell of the electron cloud are called valence electrons and have the highest energy.

Valence electrons determine the chemical properties of an elements.

20. Which one among the following is used in bleaching of paper?

Correct Answer: (a) Chloride
Solution:Chloride is used in bleaching of paper.

Chloride functions as a bleaching agent during the manufacturing process of paper.

Chlorine dioxide is used to make paper and works as a bleaching agent for wood pulp.