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Question 1

Neopentane is

Answer 1

2,2- dimethylpropane

Question 2

1 mole of any gas at STP occupied how much volume?

Answer 2

22.4L

Question 3

Atomic spectrum of hydrogen

Answer 3

SERIES n1 spectral region

• Lyman 1 UV
• Balmer 2 Visible
• Paschen 3 Infrared
• Brackett 4 Infrared
• Pfund 5 Infrared
• Humphrey 6 Far infrared

Question 4

Rydberg formula for hydrogen

Answer 4

1/ λ = Rₕ (1/n₁² - 1/n₂²)

-Rₕ: rydberg constant
-n₁:energy level

Question 5

Possible number of spectral lines when an electron returns from
n₂ –› n₁

Answer 5

(n₂ - n₁)(n₂ - n₁ +1)/ 2

Question 6

What are isoelectronic species?

Answer 6

Any two or more atoms, ions, or molecules that have the same number of electrons

Question 7

Molecular orbital order for atoms having Z ≤ 7

Answer 7

σ(1s) < σ∗(1s) < σ(2s) < σ∗(2s) < π(2p_x) = π(2p_y) < σ(2p_z) < π∗(2p_x) = π∗(2p_y) < σ∗(2p_z)

Question 8

Molecular orbital order for atoms having Z ≥ 8

Answer 8

σ(1s) < σ∗(1s) < σ(2s) < σ∗(2s) < σ(2p_z) < π(2p_x) = π(2p_y) < π∗(2p_x) = π∗(2p_y) < σ∗(2p_z)

Question 9

Electron withdrawing groups

Answer 9

• NO2
• CN
• COOH
• CHO
• CONH2

Question 10

What is a heterocyclic compound?

Answer 10

cyclic compound that has atoms of at least two different elements as members of its ring

Question 11

What is electron gain enthalpy?

Answer 11

Electron gain enthalpy of an element is the energy released when a neutral isolated gaseous atom accepts an extra electron to form the gaseous negative Ion i.e. anion.

Question 12

Stationary phase in paper chromatography

Answer 12

Water

Question 13

How is conjugate acid formed?

Answer 13

By accepting a proton (H+)

Question 14

Angular nodes

Answer 14

planar areas around the nucleus where the probability of finding an electron is zero

• s: 0
• p: 1
• d: 2
• f: 3

Question 15

Shape and hybridization of BF3 molecule

Answer 15

• Trigonal planar
• sp²

                F
                |
                B 
             /      \
           F         F

Question 16

In kjeldahls method, nitrogen in the organic compound is quantitatively converted to

Answer 16

Ammonium sulphate
(NH₄)₂SO₄

Question 17

Dipole moment of BF₃

Answer 17

Zero

Because the resultant of any two bonds is equal and opposite to the third bond

Question 18

Metamerism

Answer 18

When bridging function groups are present. Like…
-O-
-CO-
-COO-
-NH-

Question 19

Tautomerism

Answer 19

• When =C (sp²) is present
• atleast 1 α Hydrogen atom

Question 20

De broglie wavelength

Answer 20

λ = h/√ (2mKE)

m: mass
h: plancks constant
KE: kinetic energy

Question 21

Amino acid which is not optically active

Answer 21

Glycine

Question 22

Reducing sugars example

Answer 22

• glucose
• fructose
• maltose