Ncer -class 11- Chemistry- unit 4- Chemical Bonding and Molecular Structure Welcome to your Ncer -class 11- Chemistry- unit 4- Chemical Bonding and Molecular Structure 1. The paramagnetic nature of oxygen molecule is best explained on the basics of Hybridisation Resonance Molecular orbital theory Valence bond theory None 2. The order of number of lone pair of xenon in following compound is. $$X_{e} F_{6} >X_{e} O F_{4} > X_{e} O_{3} $$ $$X_{e} OF_{6} >X_{e} O F_{4} > X_{e} OF_{3} $$ $$X_{e} F_{6} >X_{e} O F_{4} > X_{e} O_{3} > X_{e} O_{4}$$ $$ X_{e} F_{2} >X_{e} F_{4} > X_{e} O_{3} > X_{e} O_{4}$$ None 3. Which of the following compound has four bond pair and one lone pair? $$X_{e}F_{4}$$ $$ICI_{4}^{-}$$ $$NH_{4}^{+}$$ $$SF_{4}$$ None 4. Which of the following is not correct? A double bond is stronger than a single bond A double bond is stronger than a single bond A double bond is shorter than a single bond A double bond is shorter than a single bond A sigma bond is weaker than 𝜋 𝑏 𝑜 𝑛 𝑑 A sigma bond is weaker than π bond A sigma bond is stronger than 𝜋 𝑏 𝑜 𝑛 𝑑 A sigma bond is stronger than π bond None 5. The number of unpaired electrons in paramagnetic diatomic molecules of an element with atomic number 16 is? 1 3 4 2 None 6. The number and types of bonds between two carbon atoms in calcium carbide is: one sigma, one pi two sigma, two pi one sigma, two pi tow sigma, one pi None 7. The correct order of increasing bond length of C−H, C−O, C−C and C=C is : 𝐶 − 𝐻 < 𝐶 = 𝐶 < 𝐶 − 𝑂 < 𝐶 − 𝐶 C−H < C=C < C−O < C−C 𝐶 − 𝑂 < 𝐶 − 𝐻 < 𝐶 − 𝐶 < 𝐶 = 𝐶 C−O < C−H < C−C < C=C C−H < C−O < C−C < C=C 𝐶 − 𝐶 < 𝐶 = 𝐶 < 𝐶 − 𝑂 < 𝐶 − 𝐻 C−C < C=C < C−O < C−H None 8. Select the correct statement : First ionization energy of Al is greater than that of gallium $$ X_{e}F_{5}^{+}$$ has disorted octahedral geometry Solubility of noble gases increases in water down the group when their size increases because London dispersion force increases If molecule has any polar bond, then it is always polar None 9. Lone pair of electrons are electrons in orbitals? Which undergo hybridization but not participate in Bond formation Which undergoes hybridization Which does not undergo hybridization Which undergoes hybridisation and participate in Bond formation None 10. Which of the following molecules has dipole moment greater than zero? Neopentane 2,2,3,3-tetramethyl butane 3-3-Diethylpentane trans-2-pentene None 11. What type of bond is formed if atom looses one or more valence electrons to give positive metal ions? Metallic Ionic Polar covalent Hydrogen bonding None 12. Which of the following molecule does not possess a permanent dipole moment? $$SO_{3}$$ $$SO_{2}$$ $$H_{2}S$$ $$CS_{2}$$ None 13. Chlorine does not show hydrogen bonding in its compounds while nitrogen shows hydrogen bonding in its compounds. Identify the correct reason. Chlorine is not as highly electronegative as nitrogen 𝐻−𝐶𝑙 bond is stronger than N−H bond Chlorine has larger size than nitrogen Chlorine has vacant d-orbitals while nitrogen has no vacant 'd' sub shell None 14. Which of the following species has maximum dipole moment $$𝐶𝐻_{3}𝐹$$ $$𝐶𝐻_{3} Br $$ $$𝐶𝐻_{3} Cl $$ $$𝐶𝐻_{3} I $$ None 15. The values of electronegativity of atoms A and B are 1.20 and 4.0 respectively. The percentage of ionic character of A and B bond is 55.3% 43% 50% 72.24% None 16. The amount of energy required to break one mole of bonds of a particular type between two atoms in a gaseous state is called lattice enthalpy ionization enthalpy Electron affinity bond enthalpy None 17. As compared to covalent compounds, electrovalent compounds generally have Low melting points and high boiling points Low melting points and low boiling points High melting points and high boiling points High melting points and low boiling points None 18. Which of the following is diamagnetic? Oxygen molecule Carbon molecule None of these Superoxide ion None 19. Which bond properties are consistent with one another? Bond order- Higher, Bond length- Shorter, Vibrational frequency- higher Bond order- Lower, Bond length - shorter, Vibrational frequency- lower Bond order- Higher, Bond length- longer, Vibrational frequency - lower Bond order- Lower, Bond length- longer, Vibrational frequency - higher None 20. In the formation of hydrogen molecule, overlapping of atomic orbitals occur which results in the pairing of electrons. These are: lone pair of electons valence shell electrons with opposite spins. valence shell electrons with same spins valence shell electrons irrespective of the spins None Time's up Please Share This Share this content Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Leave a Reply Cancel replyCommentEnter your name or username to commentEnter your email address to commentEnter your website URL (optional) Save my name, email, and website in this browser for the next time I comment.
