Covalent Bond

Q. The ionic product of water at 25^° C is 10-14. Itsionic product at 90^° C will be(1) 1 x 10-14(2) 1x 10-16(3) 1 x 10-20(4) 1x 10-12

Q.

A CO₂ molecule contains:

1. Four pi bonds

2. Two sigma and two pi bonds

3. Three sigma and one pi bond

4. Four sigma bonds

Q. Why cf3 free radical has sp3 hybridisation but ch3 free radical has sp2 hybridisation

Q. If dipole moment of HI is 0.38 D and bond lengthof HI is 1.6 A, then percentage covalent characterin HI bond is(1) 4.95%(2) 5.9%(3) 95.05%(4) 47.5%

Q.

Identify the most stable species in the following set of ions giving reasons:

$A$:


$B$:

Q. bond order of k2 and Na2O2

Q.

Match the ions given in Column I with their nature given in Column II

	Column I		Column II
A		$\left(i\right)$	Stable due to resonance
B		$\left(ii\right)$	Destabilised due to inductive effect
C		$\left(iii\right)$	stabilised by hyperconjugation
D		$\left(iv\right)$	A secondary carbocation

Q. which among the given pairs does not have identical bond order o2 2- and F2 N2 and CO CO and NO N2 and NO+

Q. If an ionic compound (molar mass of compoind is 60 g/mol) crystallises in fcc lattoce with unit cell edge length 5 A° then density of unit cell(in g/cm³) if it has 5% schottky defects is

Q. Calculate the energy of a photon of wavelength 0.5 A

Q. 5. In Which one of the Following Molecules the central Atom does not use vacant Orbital :- (1) Al2Cl6 (2) BeCl2(solid) (3) Si2H6 (4) B2H6

Q. A2 B dissociates as A2B(s)gives 2A(g) + B(g)At equilibrium total pressure is P then Kp of the reaction is2/9p2, (2)4/9p3, (3)4/27p3, 4p

Q. Which of the following xenon compounds have the same no. of lone pairs as there are in I_3^-? (1) XeO_4 (2) XeF_4 (3) XeF_2 (4) XeO_3

Q.

The hydrogen bond is shortest in

1. N - H .......O

2. F - H ...........O

3. F - H ........F

4. N - H.........F

Q. which bond is strongest between ionic bond and covalent bond

Q. which sequence correctly describes relative bond strength of oxygen molecule, superoxide ion and peroxide ion? (1) O_2O_2^->O_2^{2-} (3)O_2>O_2^->O_2^{2-} (4) O_2>O_2^->O_2^{2-

Q.

The heat of hydrogenation of hexene is 127 K J/ mole .When a second double bond is introduced in the molecule, the heat of hydrgenation of the diene is found to be 23KJ / mole. The diene is most likely to be

1. Hexa - 1, 4 - diene

2. Hexa - 1, 3 - diene

3. Hexa - 1, 5 - diene

4. Hexa - 1, 2 - diene

Q. an organic compound has 5 c=c bond .HEAT OF HYDROGENATION OF C=C BOND IS 28.6Kcal EXPERIMENTAL VALUE OF HEAT OF HYDROGENATION IS 98Kcal MOL-1 .THE RESONANCE ENERGY IS

Q. 38. What is the highest occupied molecular orbital in NO+ ?

Q. bond angle order of I3+, ICL2+, IBR2

Q. Why is third ionization energy of phosphorus greater than third ionization energy of aluminiu

Q. Assertion- multiple bond between two bonded atoms can have more than three bonds. Reason- multiple bonds between two bonded atoms can not have more than two pi bonds

Q. If we consider bond strenght of pi bond as follows -- 2p pi - 2p pi > 2p pi - 3p pi Why does bond strength of pi bond decrease as dis†an ce increases from the nucleus ?

Q. the correct order of homolytic bond fission(dissociation)energy for ch4, c2h6, ch3br

Q. 14. which of the following has lowest melting point? a)CaBr2 b)CaF2 c)CaCl2 d)Cal2

Q.

When there is breaking of bonds in such a way that the shared pair of electrons remains with one of the fragments it is termed as:

1. Geometrical isomerism

2. Homolytic cleavage

3. Heterolytic cleavage

4. Metamerism

Q. most electronegative carbon atom is present in a) Propane b) Propene c) Propyne d) Methae

Q.

Q. 30.Which molecule has minimum bond angle _NH3 , H2O , AsH3 , CH4

Q. If the temperature of the Sun were to increase from T to 2T and its radius from R to 2R, then the ratio of the radiant energy received per unit area per unit time on earth to what it was previously, will be-1)4, 2)16, 3)32, 4)64.