13. Which of the following does not have S – S bond? (A) S2 O2 4
2 (C) S2 O5
2 (B) S2 O3
2 (D) S2 O7
14. KF combines with HF to form KHF2 . The compound contains the species (A) K , F , H (C) K and HF2 ions
(B) K , F , HF (D) K , H
+ +
15. When I2 is passed through KCl, HF, KBr (A) Cl2 and Br2 are evolved (C) Cl2, Br2 F2 are evolved
(B) Cl2 is evolved (D) none of these
16. The hybridization in atomic orbitals of nitrogen in NO2 , NO3 and NH are 4
(A) sp, sp3 and sp2 respectively (C) sp , sp and sp3 respectively
2
(B) sp, sp2 and sp3 respectively (D) sp , sp3 and sp respectively
2
17. Oxygen is not evolved when conc. H2SO4 reacts with (A) KMnO4 (B) MnO2 (C) K 2Cr2O7 (D) CuSO4 18. Nitrogen dioxide is released by heating (A) Pb NO3 2 (C) NaNO2 19. Substance soluble in NH3 is (A) Al(OH)3 (C) Cr(OH)3
(B) KNO3 (D) NaNO3
(B) Fe(OH)3 (D) Cu(OH)2
20. A substance on treatment with dilute H2SO4 liberates a colourless gas which produces (i) turbidity with baryta water and (ii) turns acidified dichromate solution green. These reactions indicate the presence of 2 (A) CO3 (B) S2
2 (C) SO3
(D) NO2
21. Nitrogen is liberated by the thermal decomposition of only (A) NH4NO2 (B) NaN3 (C) (NH4)2Cr2O7 (D) all the three 21. Zinc blende is concentrated by (A) Electromagnetic process (C) Distillation 22. In the alumina thermite process Al acts as (A) an oxidising agent (C) a reducing agent (B) Calcination process (D) Froth floatation process
(B) a flux (D) a solder
23. Of the following the metals that can not be obtained by electrolysis of the aqueous solution of their salts are (A) Ag (B) Mg (C) Cu (D) None of these