Tamil nadu +2 chemistry – important one mark question

                                                          Atomic structure -  Set 3

15.       The hybridization in co₃^2- ion is

(a)        sp²                    (b)        sp³                    (c)        sp         (d)        sp³d

16. Which of the following molecular orbital has the lowest energy

(a)        σ₂p_z                   (b)        π*2p_y    (c)        σ*₂p_z     (d)        σ*2s

17. Which one  of the following is paramagnetic in nature?

(a) H₂                (b)He₂               (c)NO                (d)N₂

18. The energy value of an electron in hydrogen atom is -82 KJmol^-1. The value of "n" is

(a)        2          (b)        3          (c)        4          (d)        5

19. The momentum of a particle which has de-Broglie wavelength of 10^-10 m (h=6.626×10^-34 kg m² s^-1) is

(a)        6.6×10^-23 kg ms^-1                        (b)        6.6×10^-24 kg ms^-1

(c)     6.6×10^-34 kg ms^-1               (d)        6.6×10³⁴ kg ms^-1

20. Which of the following  indicates that a molecule is stable

(a) N_b=N_a=0        (b) N_b=N_a    (c)  N_b>N_a     (d)   N_b<N_a

21. The  uncertainity in the momentum of an electron is 1.0×10-5 kg ms-1. The uncertainity in its position will be (h= 6.626×1034 Js)

(a) 1.05×10^-28 m (b) 1.05×10^-26 m (c) 5.27×10^-30 m (d) 5.25×10^-28 m