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 order of number of lone pair of xenon in following compound is. $$X_{e} OF_{6} >X_{e} O F_{4} > X_{e} OF_{3} $$ $$X_{e} F_{6} >X_{e} O F_{4} > X_{e} O_{3} $$ $$ X_{e} F_{2} >X_{e} F_{4} > X_{e} O_{3} > X_{e} O_{4}$$ $$X_{e} F_{6} >X_{e} O F_{4} > X_{e} O_{3} > X_{e} O_{4}$$ None 2. Which of the following is not correct? A sigma bond is weaker than 𝜋 𝑏 𝑜 𝑛 𝑑 A sigma bond is weaker than π bond A double bond is stronger than a single bond A double bond is stronger than a single bond A sigma bond is stronger than 𝜋 𝑏 𝑜 𝑛 𝑑 A sigma bond is stronger than π bond A double bond is shorter than a single bond A double bond is shorter than a single bond None 3. Chlorine does not show hydrogen bonding in its compounds while nitrogen shows hydrogen bonding in its compounds. Identify the correct reason. 𝐻−𝐶𝑙 bond is stronger than N−H bond Chlorine is not as highly electronegative as nitrogen Chlorine has vacant d-orbitals while nitrogen has no vacant 'd' sub shell Chlorine has larger size than nitrogen None 4. In the formation of hydrogen molecule, overlapping of atomic orbitals occur which results in the pairing of electrons. These are: valence shell electrons with same spins valence shell electrons with opposite spins. lone pair of electons valence shell electrons irrespective of the spins None 5. 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 50% 72.24% 55.3% 43% None 6. Which of the following is diamagnetic? Oxygen molecule Carbon molecule Superoxide ion None of these None 7. Which of the following molecules has dipole moment greater than zero? Neopentane trans-2-pentene 2,2,3,3-tetramethyl butane 3-3-Diethylpentane None 8. The correct order of increasing bond length of C−H, C−O, C−C and C=C is : C−H < C−O < C−C < C=C 𝐶 − 𝐶 < 𝐶 = 𝐶 < 𝐶 − 𝑂 < 𝐶 − 𝐻 C−C < C=C < C−O < C−H 𝐶 − 𝑂 < 𝐶 − 𝐻 < 𝐶 − 𝐶 < 𝐶 = 𝐶 C−O < C−H < C−C < C=C 𝐶 − 𝐻 < 𝐶 = 𝐶 < 𝐶 − 𝑂 < 𝐶 − 𝐶 C−H < C=C < C−O < C−C None 9. Which of the following molecule does not possess a permanent dipole moment? $$SO_{3}$$ $$H_{2}S$$ $$SO_{2}$$ $$CS_{2}$$ None 10. The number and types of bonds between two carbon atoms in calcium carbide is: tow sigma, one pi one sigma, two pi one sigma, one pi two sigma, two pi None 11. Lone pair of electrons are electrons in orbitals? Which undergoes hybridization Which undergoes hybridisation and participate in Bond formation Which undergo hybridization but not participate in Bond formation Which does not undergo hybridization None 12. What type of bond is formed if atom looses one or more valence electrons to give positive metal ions? Polar covalent Ionic Metallic Hydrogen bonding None 13. Which bond properties are consistent with one another? Bond order- Higher, Bond length- Shorter, Vibrational frequency- higher Bond order- Lower, Bond length- longer, Vibrational frequency - higher Bond order- Lower, Bond length - shorter, Vibrational frequency- lower Bond order- Higher, Bond length- longer, Vibrational frequency - lower None 14. Which of the following species has maximum dipole moment $$𝐶𝐻_{3}𝐹$$ $$𝐶𝐻_{3} I $$ $$𝐶𝐻_{3} Br $$ $$𝐶𝐻_{3} Cl $$ None 15. As compared to covalent compounds, electrovalent compounds generally have Low melting points and low boiling points High melting points and low boiling points High melting points and high boiling points Low melting points and high boiling points None 16. The paramagnetic nature of oxygen molecule is best explained on the basics of Valence bond theory Hybridisation Resonance Molecular orbital theory None 17. Which of the following compound has four bond pair and one lone pair? $$SF_{4}$$ $$X_{e}F_{4}$$ $$ICI_{4}^{-}$$ $$NH_{4}^{+}$$ None 18. Select the correct statement : First ionization energy of Al is greater than that of gallium 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 $$ X_{e}F_{5}^{+}$$ has disorted octahedral geometry None 19. The number of unpaired electrons in paramagnetic diatomic molecules of an element with atomic number 16 is? 1 3 2 4 None 20. The amount of energy required to break one mole of bonds of a particular type between two atoms in a gaseous state is called ionization enthalpy bond enthalpy Electron affinity lattice enthalpy 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.
