The oxidation number of Cr in Cr₂O₇^2- _______ is

(a)

+6

(b)

-6

(c)

+7

(d)

-7

The value of Avogadro Number N is equal to ___________.

(a)

2.24 x 10^-2L

(b)

22400 cm^-3

(c)

6.023 x 10^-23

(d)

6.023 x 10²³

The radius of which of the following is same as that of the first Bohr orbit of hydrogen atom?

(a)

He⁺ (n = 2)

(b)

Li⁺² (n = 2)

(c)

Li^-2 (n = 3)

(d)

Be⁺³ (n = 2)

The element with atomic number 31 belongs to _____

(a)

s-block

(b)

p-block

(c)

d-block

(d)

f-block

Hydrogen accepts an electron to attain the inert gas configuration. In this way it resembles __________

(a)

chalcogens

(b)

halogens

(c)

transition metals

(d)

alkali metals

Which metal does not liberate H₂ gas from dilute aqueous hydrochloric acid at 298 K?

(a)

Mg

(b)

Zn

(c)

Al

(d)

Cu

Consider the following statements.
(i) Lithium does not have d-orbitals.
(ii) Lithium carbonate is more soluble than sodium carbonate in water.
(iii) The second ionization enthalpy of alkali metals are zero.
Which of the above statements is/are not correct?

(a)

(i) only

(b)

(ii) only

(c)

(ii) and (iii)

(d)

(i), (ii) and (iii)

273K is equal to ______________ degree centigrade.

(a)

0

(b)

100

(c)

373

(d)

1

Consider the following statements.
(i) All the gases have higher densities than liquids and solids.
(ii) All gases occupy zero volume at absolute zero.
(iii) At very low pressure all gases exhibit ideal behaviour.
Which of the above statement is/are not correct?

(a)

(i) only

(b)

(ii) only

(c)

(iii) only

(d)

(ii) and (iii) only

For the reaction, X₂ O₄(l) \(\rightarrow\) 2 XO₂ (g), \(\Delta\)U=2.1 Kcal, \(\Delta\)S = 20 cal K^-1 at 300 K. Hence,\(\Delta\)G is:

(a)

2.7 Kcal

(b)

-2.7 Kcal

(c)

9.3 K.=cal

(d)

-9.3 Kcal