Miscellaneous And Useful Chemical Compounds (Part-III)

  1. (d) Radiometer

 

Total Questions: 50

11. What is the product formed when sodium bicarbonate is heated [S.S.C. Online Graduate Level (T-I) 29.08.2016 (Shift-I)]

Correct Answer: (a) Sodium Carbonate
Solution:When sodium bicarbonate (NaHCO₃) is heated excessively, i.e., above 80 °C, it decomposes to form sodium carbonate, water, and carbon dioxide gas.
2NaHCO₃ → Na₂CO₃ + H₂O + CO₂

12. Which of the following acids is called the king of acids? [S.S.C. Online MTS (T-I) 15.10.2017 (Shift-II)]

Correct Answer: (d) Sulphuric acid
Solution:Sulfuric acid is called the 'king of acids' because it is a very strong acid and has a very high level of corrosion.

13. What is the formula of potassium ion in an ideal gas state? [S.S.C. Online CHSL (T-I) 21.01.2017 (Shift-II)]

Correct Answer: (a) K⁺
Solution:The atomic number of potassium (K) is 19. Therefore, it has a total of 19 electrons in its orbitals in the normal state. According to the order of filling of its orbitals, the configuration of potassium will be 1s², 2s², 2p⁶, 3s², 3p⁶, and 4s¹, but the K⁺ ion formed by the loss of 1 electron from the 4s¹ orbital now has 18 electrons and hence the configuration of the K⁺ ion. The inert gas becomes similar to argon (atomic number 18).

14. Which of the following is NOT a noble gas? [S.S.C. Online MTS (T-I) 22.10.2021 (Shift-I)]

Correct Answer: (a) Oxygen
Solution:Argon, krypton, and neon are all inert gases, which behave as ideal gases over a wide range of temperatures, whereas oxygen cannot behave as an ideal gas over a large range of temperatures.

15. Which among the following is an example of solid sol? [S.S.C. Online Graduate Level (T-I) 8.08.2017 (Shift-I)]

Correct Answer: (c) Coloured gemstones
Solution:In physical chemistry, a sol is a type of colloid in which very fine particles are distributed in a continuous medium. Colored (gemstone) stone is also a type of solid sol, in which fine particles are distributed in a solid continuous medium.

16. The state in which molecular attractions are very strong is: [S.S.C. Online MTS (T-I) 6.10.2017 (Shift-I)]

Correct Answer: (a) Solid
Solution:Molecular attraction means the force of attraction acting between the molecules is greatest in the solid state of matter. In the solid state, the molecules of matter are arranged in a definite order by staying very close and are bound to each other by a strong force of attraction.

17. Which of the following is used for the ripening of fruits? [S.S.C. Online C.P.O.S.I. (T-I) 3.07.2017 (Shift-II)]

Correct Answer: (b) Ethylene
Solution:Ethylene gas is used for ripening fruits. It is an unsaturated hydrocarbon. The chemical formula of ethylene is C₂H₄. It is a compound containing a carbon-carbon double bond. Its structure is as given below—
H H
C = C
H H

18. Whitewashed walls appear to be shiny after three to four days due to the formation of: [S.S.C. Online MTS (T-I) 20.10.2021 (Shift-III)]

Correct Answer: (d) Calcium carbonate
Solution:When painted walls are coated with lime Ca(OH)₂, calcium carbonate (CaCO₃) is formed by the action of atmospheric carbon dioxide (CO₂). This action goes like this—
Ca(OH)₂ + CO₂ → CaCO₃ + H₂O
CaCO₃ (calcium carbonate) is a white salt, so the wall becomes shinier.

19. Name the gas used in the preparation of bleaching powder. [S.S.C. Online Graduate Level (T-I) 1.09.2016 (Shift-I)]

Correct Answer: (d) Chlorine
Solution:The gas used in the preparation of bleaching powder is chlorine (Cl₂). Chlorine gas is passed through calcium hydroxide (Ca(OH)₂) solution to make bleaching powder and the following reaction takes place—
Ca(OH)₂ + Cl₂ → CaOCl₂ + H₂O
(bleaching powder)

20. What is the common name of Ca(OCl)₂? [S.S.C. Online C.P.O.S.I. (T-I) 7.07.2017 (Shift-I)]

Correct Answer: (b) Bleaching powder
Solution:Ca(OCl)₂ is a common name for bleaching powder, whose chemical name is calcium hypochlorite. It is an inorganic compound, which is white in color. This gives off a strong chlorine smell. It is also used to make chloroform and chlorine gas.