Haryana Board (HBSE) Class 11 Chemistry Half Yearly Question Paper 2023 Answer Key
Instructions :
• All questions are compulsory.
• Questions (1-15) carry 1 mark each.
• Questions (16-18) carry 2 marks each.
• Questions (19-21) carry 3 marks each.
• Questions (22-23) carry 5 marks each.
1. How many significant figures are there in 0.0036?
(a) 2
(b) 3
(c) 4
(d) 5
Answer – (a) 2
2. Which of the following is isoelectronic with CO?
(a) NO
(b) SnCl2
(c) N2
(d) NO2
Answer – (c) N2
3. Enthalpy of Reaction in a endothermic process is :
(a) Positive
(b) Negative
(c) Zero
(d) None of these
Answer – (a) Positive
4. Temperature at which Celsius and Fehrenheit scale give the same reading :
(a) 40°C
(b) -40°C
(c) 27°C
(d) None of above
Answer – (d) -40°C
F = (9/5)×C + 32
5. Which element has most negative electron gain enthalpy?
(a) F
(b) Br
(c) Cl
(d) I
Answer – (c) Cl (chlorine)
6. Which of the following pairs has diagonal relationship?
(a) Be and Al
(b) Be and Mg
(c) Li and Na
(d) B and Al
Answer – (a) Be (beryllium) and Al (aluminium)
7. Which of the following molecules has pyramidal shape?
(a) NH3
(b) PCI5
(c) H2O
(d) SF6
Answer – (a) NH3
8. Which type of intermolecular forces of attraction exist among H2O molecules?
(a) Vander Waal force
(b) Hydrogen bonding
(c) Dipole dipole interaction
(d) None of these
Answer – (b) Hydrogen bonding
9. What is the mass of 0.1 mole of glucose (C6H12O6)
(a) 18 g
(b) 1.8 g
(c) 108 g
(d) 180 g
Answer – (a) 18 g
Molar Mass = 6×12 + 12×1 + 6×16 = 72 + 12 + 96 = 180 g/mol
10. What is hybridisation of B in BF3 molecule?
(A) SP
(B) SP2
(C) SP3
(D) SP3d2
Answer – (B) SP2
11. Write formula for conjugate base of HCO3–.
Answer : CO32–
12. What is the value for compressibility factor for ideal gas?
Answer : Z = 1
13. Write expression for equilibrium constant for the following reaction :
N2 + 3H2 ⇌ 2NH3
Answer : K = [NH3]2 / [N2][H2]3
14. Name the type of system in which neither matter nor energy is exchanged with surroundings.
Answer – Isolated system
15. What is general electronic configuration for p block elements?
Answer : ns2np1–6
16.