CHEMISTRY (Part-V) (Railway)

21. The conversion of ethanol to ethanoic acid is an example of which of the following reaction? [RRB Group 'D' CBT Exam, 22.08.2022 (Shift-III)]

(1) Combustion reaction
(2) Addition reaction
(3) Oxidation reaction
(4) Substitution reaction

Correct Answer: (3) Oxidation reaction

22. In the given reaction,__________ acts as a reducing agent. [RRB Group 'D' CBT Exam, 22.08.2022 (Shift-III)]

Fe₂O₃ + 3CO → 2Fe + 3CO₂

(1) Fe
(2) CO₂
(3) Fe₂O₃
(4) CO

Correct Answer: (3) Fe₂O₃

23. What is the correct order of metallic character of the following metals? [RRB Group 'D' CBT Exam, 22.08.2022 (Shift-III)]

(1) Na < Mg < Cs < Ba
(2) Cs < Ba < Na < Mg
(3) Mg < Na < Ba < Cs
(4) Ba < Cs < Mg < Na

Correct Answer: (3) Mg < Na < Ba < Cs

24. Consider the below statements and identify the correct answer. [RRB Group 'D' CBT Exam, 22.08.2022 (Shift-III)]

Statement I: Ionic compounds are generally brittle and break into pieces when pressure is applied.

Statement II: Ionic compounds have low melting and boiling points.

(1) Both the statements are true.
(2) Statement-II is true, and Statement-I is false.
(3) Both the statement are false.
(4) Statement-I is true, and Statement-II is false.

Correct Answer: (4) Statement-I is true, and Statement-II is false.

25. Consider the statements given below and identify the correct answer. [RRB Group 'D' CBT Exam, 22.08.2022 (Shift-III)]

Statement I: Washing soda is produced from sodium chloride.

Statement II: It attacks dirt and grease to form water soluble products, which are then washed away on rinsing with water.

(1) Both the statements are true.
(2) Statement-II is true, and Statement-I is false.
(3) Both the statements are false.
(4) Statement-I is true, and Statement-II is false.

Correct Answer: (2) Statement-II is true, and Statement-I is false.

26. Which of the following triads is NOT a Dobereiner's triad? [RRB Group 'D' CBT Exam, 22.08.2022 (Shift-III)]

(i) Li, Na, K

(ii) Ca, Sr, Ba

(iii) N, P, Sb

(iv) Cl, Br, I

(1) Only iii
(2) Only i
(3) Only ii
(4) Only iv

Correct Answer: (1) Only iii

27. In the reaction ZnO + C → Zn + CO: [RRB Group 'D' CBT Exam, 22.08.2022 (Shift-III)]

(1) ZnO is reduced to Zn
(2) Zn does not undergo redox reaction.
(3) ZnO is oxidized to Zn
(4) Carbon is reduced to CO

Correct Answer: (1) ZnO is reduced to Zn

28. The insoluble substance formed in a solution during a chemical reaction is known as _______. [RRB Group 'D' CBT Exam, 23.08.2022 (Shift-I)]

(1) soluble salt
(2) aqueous solution
(3) residue
(4) precipitate

Correct Answer: (4) precipitate

29. Consider the below statements and identify the correct answer. [RRB Group 'D' CBT Exam, 23,08.2022 (Shift-I)]

Statement-I: Most carbon compounds are poor conductors of electricity.

Statement II: Carbon compounds have low melting and boiling points.

(1) Both the statements are true
(2) Both the statements are false.
(3) Statement-II is true, and Statement-I is false
(4) Statement-I is true, and Statement-II is false.

Correct Answer: (1) Both the statements are true

30. Consider the statements below and identify the correct answer. [RRB Group 'D' CBT Exam, 23.08.2022 (Shift-I)]

Statement- I: Modern periodic table has 18 vertical columns known as groups.

Statement-II: Modern periodic table has 7 horizontal rows known as periods.

(1) Both statements are incorrect
(2) Both statements are correct.
(3) Statement II is correct. statement I is incorrect.
(4) Statemente 1 is correct. statement II is incorrect.

Correct Answer: (2) Both statements are correct.