SAMPLE QUESTIONS
1. If the shortest wavelength of hydrogen atom in Lyman series is x, then longest wavelength in Balmer series of He
^{+} is
a) $\frac{9x}{5}$
b) $\frac{36x}{5}$
c) $\frac{x}{4}$
d) $\frac{5x}{9}$
2. The gas liberated on heating a mixture of two salts with NaOH , give a reddish brown presipitate with an alkaline solution of K
_{2}HgI
_{4}. The aqueous solution of the mixture on treatment with BaCl
_{2} gives a white precipitate which is sparingly soluble in conc. HCl . On heating the mixture with K
_{2}Cr
_{2}O
_{7} and conc. H
_{2}OSO
_{4}, red vapours are proced. The aqueous solution of mixture gives a deep blue colouration with potassium ferricyanide solution. Then, identify the radicals in the given mixture.
a) $NH_{4}^{+}, Fe^{3+}, SO_{4}^{2-}, NO_{2}^{-}$
b) $CO_{3}^{2-}, Fe^{2+}, SO_{4}^{-}, Cl^{-}$
c) $NH_{4}^{+}, Fe^{2+} , SO_{4}^{2-}, Cl^{-}$
d) $NH_{4}^{+}, Ca^{2+}, SO^{2-}_{4}, Cl^{-}$