According to molecular orbital theory, what is the bond order of nitrogen, N. 2? The C — O — C bond in ethers like the C — OH bond in alcohols is quite strong. XeF2 has a total bond energy of 267.8 kJ/mol (64.0 kcal/mol), with first and second bond energies of 184.1 kJ/mol (44.0 kcal/mol) and 83.68 kJ/mol (20.00 kcal/mol), respectively. Assertion (A) : Though the central atom of both NH. Match the items given in Column I with examples given in Column II. The product is a solid. Many such reactions with products of the form [Mx(XeF2)n](AF6)x have been observed, where M can be calcium, strontium, barium, lead, silver, lanthanum, or neodymium and A can be arsenic, antimony or phosphorus. describe this process:[36], The mechanism of the etch is as follows. In the presence of liquid HF, dark green crystals can be precipitated from the green solution at −30 °C: X-ray crystallography indicates that the Xe–Xe bond length in this compound is 309 pm, indicating a very weak bond. To get fastest exam alerts and government job alerts in India, join our Telegram channel. Chemistry Class 11 Important Questions are very helpful to score high marks in board exams. You also get idea about the type of questions and method to answer in your Class 11th examination. Why is there difference in bond enthalpy of O—H bond in ethanol (C. Match the species in Column I with the type of hybrid orbitals in Column II. The very first ETF was launched in Canada in 1990 and the industry has come a long way since then. Which molecule/ion out of the following does not contain unpaired electrons? (i) In the formation of dioxygen from oxygen atoms 10 molecular orbitals will be formed. Explain the formation of a chemical bond. Bond distances are measured in Ångstroms (1 Å = 10 –10 m) or picometers (1 pm = 10 –12 m, 100 pm = 1 Å). Also indicate the total number of sigma and pi bonds in this molecule. Assertion (A): Among the two O–H bonds in H2O molecule, the energy required to break the first O–H bond and the other O–H bond is the same. This page was last edited on 8 February 2021, at 16:30. [24][25] With fluoride ion acceptors, it forms XeF+ and Xe2F+3 species which are even more powerful fluorinators.[1]. A bond distance (or bond length) is the distance between the nuclei of two bonded atoms along the straight line joining the nuclei. Xenon difluoride is a powerful fluorinating agent with the chemical formula XeF2, and one of the most stable xenon compounds. Assertion (A) : Sodium chloride formed by the action of chlorine gas on sodium metal is a stable compound. (i) NaCl being an ionic compound is a good conductor of electricity in the solid state. A double bond forms when two pairs of electrons are shared between a pair of atoms, as between the carbon and oxygen atoms in CH 2 O (formaldehyde) and between the two carbon atoms in C 2 H 4 (ethylene): A triple bond forms when three electron pairs are shared by a pair of atoms, as in carbon monoxide (CO) and the cyanide ion (CN –): In which of the following substances will hydrogen bond be strongest? Which among the following are dimagnetic? Bond order for O2+ = 10-5/2 = 2.5 Bond order for O-2 = 10-7/2 = 1.5 According to Molecular Orbital Theory, the greater the bond order greater is the bond energy. Such is the case for CO 2, a linear molecule (Figure \(\PageIndex{8a}\)). This agrees with the prediction of VSEPR theory, which predicts that there are 3 pairs of non-bonding electrons around the equatorial region of the xenon atom. (ii) Represent diagrammatically the bond moments and the resultant dipole moment in CO 2, NF 3 and CHCl 3. Use the molecular orbital energy level diagram to show that N. Briefly describe the valence bond theory of covalent bond formation by taking an example of hydrogen. 66. a. Four of the fluorine atoms are attributed to the four xenon difluoride ligands while the other two are a pair of cis-AsF−6 ligands.[22]. Structures of molecules of two compounds are given below : (a) Which of the two compounds will have intermolecular hydrogen bonding and which compound is expected to show intramolecular hydrogen bonding. Brazzle, Dokmeci, et al. [13] Williamson reported that the reaction works equally well at atmospheric pressure in a dry Pyrex glass bulb using sunlight as a source. A bond angle is the angle between any two bonds that include a common atom, usually measured in degrees. 65. 1 b. Fluorine is the main etchant in the silicon etching process. If you are looking to invest using Exchange-Traded Funds (ETFs), this post covers some of the best ETFs you can buy and hold in your portfolio in Canada. [12] Shortly after these reports, Weeks, Cherwick, and Matheson of Argonne National Laboratory reported the synthesis of XeF2 using an all-nickel system with transparent alumina windows, in which equal parts xenon and fluorine gases react at low pressure upon irradiation by an ultraviolet source to give XeF2. (ii) Which of these compounds will have the highest dipole moment? It is important to be able to predict and understand the molecular structure of a molecule because many of the properties of a substance are determined by its geometry. A subsequent nucleophile attack by a strong nucleophile such as Br– as I– ion on the less hindered carbon atom of the protonated : + ... XeF2 + PF5 ——— [XeF… In which of the following molecule/ion all the bonds are not equal? Here we have provided NCERT Exemplar Problems Solutions along with NCERT Exemplar Problems Class 11. Group the following as linear and non-linear molecules : Elements X, Y and Z have 4, 5 and 7 valence electrons respectively. Predict the shapes of the following molecules on the basis of hybridisation. Which of the following has the highest dipole moment? NCERT TEXTBOOK QUESTIONS SOLVED. (i) A and R both are correct, and R is correct explanation of A. i) Discuss the significance/ applications of dipole moment. A bond angle is the angle between any two bonds that include a common atom, usually measured in degrees. (i) A and R both are correct, and R is the correct explanation of A. Isostructural species are those which have the same shape and hybridisation. (iii) Bond strength of N2 is maximum amongst the homonuclear diatomic molecules belonging to the second period.