7.5 g of a gas occupies a volume of 5.6 litres at 0° C and 1 atm pressure. The gas is ________.

(a)

NO

(b)

N₂O

(c)

CO

(d)

CO₂

Rusting of iron articles is an example of ___________ reaction

(a)

Combustion

(b)

decomposition

(c)

redox

(d)

hydrolysis

Which of the following is a mono-atomic molecule?

(a)

Hydrogen

(b)

Oxygen

(c)

Sodium

(d)

Ozone

The oxidation number of Cr in K₂Cr₂O₇ is ___________.

(a)

+4

(b)

+6

(c)

0

(d)

+7

The number of nodes in s orbital of any energy level is equal to _________

(a)

n

(b)

2n²

(c)

n-1

(d)

n-2

Which of the following is the expected configuration of Cr (Z = 24)?

(a)

1s² 2s² 2p⁶ 3s² 3p⁶ 3d⁴ 4s²

(b)

1s² 2s² 2p⁶ 3s² 3p⁶ 3d⁵ 4s¹

(c)

1s² 2s² 2p⁶ 3s² 3p⁶ 3d⁶

(d)

1s² 2s² 2p⁶ 3s² 3p⁶ 3d⁵ 4s³

d-block elements form ____ compounds.

(a)

ionic

(b)

covalent

(c)

Coordinate

(d)

both (a) and (b)

In the following the element with the highest ionisation energy is _______

(a)

[Ne]3s²3p1

(b)

[Ne]3s²3p³

(c)

[Ne]3s²3p²

(d)

[Ne]3s²3p4

Consider the following statements.
(i) d-block elements show variable oxidate states.
(ii) Mostly d-block elements form colourless compounds.
(iii) Mostly d-block elements are diamagnetic due to paired electrons.
Which of the above statement is/are not correct?

(a)

(i) only

(b)

(ii) only

(c)

(i) and (ii)

(d)

(ii) and (iii)

Which of the following possess almost same properties due to lanthanide contraction?

(a)

Zr,HF

(b)

Na,K

(c)

Zn,Cd

(d)

Ag,Au

Considering the elements F, CI, O and N, the correct order of their chemical reactivity in terms of oxidizing property is_____

(a)

F > CI > O > N

(b)

F > O > CI > N

(c)

CI > F > O > N

(d)

0 > F > N > CI

Consider the isoelectronic species Na⁺, Mg²⁺, F^- and O^2-. The correct order of increasing length of their radius is ______________

(a)

F^- < O^2- < Mg²⁺< Na⁺

(b)

Mg²⁺ < Na⁺ < F^- < O^2-

(c)

O^2- < F^- < Na⁺ < Mg²⁺

(d)

O^2- < F^- < Mg²⁺ < Na⁺

The element with highest electron affinity belongs to___________.

(a)

period 1 group 1

(b)

period 3 group 17

(c)

period 2 group 17

(d)

period 2 group 16

The number of neutrons in  hydrogen atom is ___________.

(a)

three

(b)

two

(c)

one

(d)

zero

Hydrogen is used in _________

(a)

hydrogenation of oils

(b)

fuel cells

(c)

gas bags for air ships

(d)

all the above

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

The maximum density of water is observed at ___________

(a)

0^oC

(b)

4^oC

(c)

11.6^oC

(d)

273^oC

CaO and NaCl have the same crystal structure and approximately the same radii. It U is the lattice energy of NaCl, the approximate lattice energy of CaO is _____________

(a)

U

(b)

2U

(c)

U/2

(d)

4U

The IUPAC name of  is ____________

(a)

2 – Bromo -3 – methyl butanoic acid

(b)

2 - methyl - 3- bromobutanoic acid

(c)

3 - Bromo - 2 - methylbutanoic acid

(d)

3 - Bromo - 2, 3 - dimethyl propanoic acid

Homolytic fission of covalent bond leads to the formation of ___________.

(a)

electrophile

(b)

nucleophile

(c)

Carbo cation

(d)

free radical

The compounds formed at anode in the electrolysis of an aquous solution of potassium acetate are __________

(a)

CH₄ and H₂

(b)

CH₄ and CO₂

(c)

C₂H₆ and CO₂

(d)

C₂H₄ and Cl₂

Identify the compound 'Z' in the following reaction
\({ C }_{ 2 }{ H }_{ 6 }O\overset { { Al }_{ 2 }{ O }_{ 3 } }{ \underset { 623\quad K }{ \longrightarrow } } X\overset { { O }_{ 3 } }{ \longrightarrow } Y\overset { Zn/{ H }_{ 2 }O }{ \longrightarrow } \left( Z \right) \)

(a)

Formaldehyde

(b)

Acetaldehyde

(c)

Formic acid

(d)

none of these

In the reaction  X is ________.

(a)

(b)

(c)

(d)

Ethylidene chloride on treatment with aqueous KOH gives ___________

(a)

acetaldehyde

(b)

ehtyleneglycol

(c)

formaldehyde

(d)

glycoxal

Assertion (A) : Oxygen plays a key role in the troposphere
Reason (R) : Troposphere is not responsible for all biological activities
i) Both (A) and R are correct and (R) is the correct explanation of (A)
ii) Both (A) and R are correct and (R) is not the correct explanation of (A)
iii) Both (A) and R are not correct
iv) (A) is correct but( R) is not correct

(a)

Both (A) and R are correct and (R) is the correct explanation of (A)

(b)

Both (A) and R are correct and (R) is not the correct explanation of (A)

(c)

Both (A) and R are not correct

(d)

(A) is correct but( R) is not correct