Nagaland Board of School Education (NBSE HSSLC) Chemistry Sample Paper 2026
The NBSE Board will upload the HSSLC 2026 question papers on its official website to help students get ready for the final exams. These papers are really useful for understanding the exam pattern, knowing the chapter‑wise marks distribution, and practicing problem‑solving. It's a good idea to attempt these papers within a fixed time so that you can improve your writing speed and manage time better in the real exam.
For the NBSE HSSLC 2026 exams, students will get 15 extra minutes just to read the question paper before starting to write. To prepare well, you can also download previous years’ question papers and sample papers from the NBSE Chemistry Sample Papers or official NBSE website. Solving these will give you a clear idea of the question style, difficulty level, and how marks are distributed.
NB/XII/CHE/1
NBSE Sample Paper: 2026
CHEMISTRY
Total marks : 70
Time : 3 hours
General instructions:
i) Approximately 15 minutes is allotted to read the question paper and revise the answers.
ii) The question paper consists of 34 questions. All questions are compulsory.
iii) Marks are indicated against each question.
iv) Internal choice has been provided in some questions.
N.B: Check that all pages of the question paper is complete as indicated on the top left side.
1. The values of Van't Hoff factors for NaCl, CaCl2, K2SO4 respectively are
(a) 2, 3, 2 (b) 2, 3, 3 (c) 1, 2, 3 (d) 2, 2, 3
2. SI unit of molar conductivity is
(a) S m−1mol−1 (b) Scm (c) cm2S−1 (d) S cm−1 m−1
3. Identify the reaction order from the rate constant
k = 4.0 × 102 L2mol−2s−1
(a) Zero order (b) First order (c) Second order (d) Third order
4. Which statement about transition elements is not correct?
(a) They form coloured compounds
(b) They show multiple oxidation states
(c) All their ions are diamagnetic
(d) They act as good catalysts
5. Which one of the following is a π-acid ligand?
(a) NO (b) NH3 (c) CN− (d) en
6. The full form of DDT is
(a) dichlorodiphenyltrichloroethane
(b) dichlorodiphenyltrichloromethane
(c) diphenyldichlorotrifluoroethane
(d) dichlorodiphenylethane
7. The IUPAC name of m-cresol is
(a) 2-methylphenol (b) 3-methylphenol (c) 4-methylphenol (d) methoxybenzene
8. Which of the following is the strongest acid?
(a) BrCH2COOH (b) ICH2COOH (c) ClCH2COOH (d) FCH2COOH
9. The reaction of phenol with benzene diazonium chloride and base is called
(a) Coupling reaction (b) Gattermann reaction (c) Sulphonation (d) Friedel-Crafts reaction
10. Rickets in children is caused due to deficiency of
(a) Vitamin A (b) Vitamin C (c) Vitamin D (d) Vitamin K
11. What is the elevation of boiling point?
12. Write the IUPAC name of [Fe(CN)6]3−
13. Why is 2-chloropropane more reactive towards SN1 than 1-chloropropane?
14. Draw the structures of the optical isomers of 2-butanol.
15. What is the name of the catalyst used in Friedel–Crafts acylation?
16. Arrange in increasing order of boiling points:
CH4, CH3OH, CH3CH2COOH
17. Differentiate between ideal and non-ideal solutions on the basis of enthalpy change.
18. Write the rate equation for the decomposition of N2O5 if it follows first order kinetics.
19. Propanoic acid is a stronger acid than ethanol. Explain.
20. How will you convert benzene into m-nitroaniline?
21. a) Identify A and B in the following sequence:
CH3CH2OH --NaCN → A --LAH → B
b) Complete the reaction:
C6H5NH2 -- Br2/CS2 → ?
22. a) Why is sucrose a non-reducing sugar?
Or
b) What are the products when maltose is hydrolysed?
23. a) Calculate the osmotic pressure of a solution prepared by dissolving 0.1 g glucose in 100 mL water at 27°C. [R = 0.0821 L atm K−1 mol−1]
Orb) Calculate the freezing point depression when 5 g urea (M = 60 g/mol) is added to 100 g water. [Kf = 1.86 K kg mol−1]
24. What type of cell is the Daniel cell? Write the anode and cathode reactions, and give the overall cell reaction.
25. a) For the reaction 2NO + Cl2 → 2NOCl, doubling [NO] quadruples the rate while doubling [Cl2] doubles the rate. What is the order with respect to each reactant?
Orb) The decomposition of N2O5 at 300K is first order. The concentration drops from 0.5 M to 0.125 M in 60 min. Calculate the rate constant.
26. Why do transition elements act as good catalysts? How do they differ from main group elements in their catalytic behaviour?
27. [FeF6]3− is high spin, [Fe(CN)6]3− is low spin. Explain why.
28. What is the Wurtz reaction? Give an example.
29. a) Write the mechanism of acid catalysed hydration of ethene to ethanol.
Orb) How are ethers prepared by Williamson synthesis?
30. Explain Hoffmann bromamide reaction with a suitable example.
31. Draw the furanose form of fructose.
32. a) A voltaic cell is set up at 25°C with the following half-cells: (0.001 M) | Zn2+(aq) | Zn (s) and (1.0 M) | Cu2+(aq) | Cu (s) Calculate Ecell. [EZn2+ ∣ Zn = –0.76 V, ECu2+ ∣ Zn = +0.34 V]
Orb) Calculate the standard cell potential for the following reaction:
Fe(s) + Cu2+(aq) → Fe2+(aq) + Cu(s)
Given E∘cell = 0.78 V
33. i) What are actinides?
ii) Write the general electronic configuration for actinides.
iii) Why is Ce4+ a good oxidising agent?
34. a) i) Write the IUPAC name of CH3COCH2CH3
ii) What is observed when acetone reacts with 2,4-DNP?
iii) Why is formic acid more acidic than acetic acid?
b) Give reasons for the following:
i) Formaldehyde undergoes Cannizzaro reaction.
ii) Acetone does not give iodoform test.
iii) Carboxylic acids have higher boiling points than aldehydes.