transitional elements. In VSEPR theory, the electron pairs on the central<br />IV. LINKED COMPREHENSION :<br />VSEPR theory is applicable to simple molecules or ions of non<br />atom are considered as point charges. Due to repulsion among the electron<br />pairs, they are arranged in space around the central atom such that the<br />repulsions are minimum. Order of repulsion among various electron pairs<br />is L.P -<br />L.P> L.P - B.P > B.P - B.P. Presence of lone pairs at the central<br />atom causes distortion to the regular shapes and deviation in bond angles.<br />17. Which of the following, the central atom has same number of lone pairs as<br />on P in PC13<br />[ ]<br />(A) BCB<br />(B) NCI (C) CC14 (D) PCOS<br />18. Which of the following molecule is planar<br />(A) NH<br />(B) NCI (C) BCI (D) PCI<br />19. Which of the following does not have a lone pair of electrons<br />(A)H-Cl (B) H-O-H (C) NH3 (D) NH.
Answers
Explanation:
Valence shell electron pair repulsion theory, or VSEPR theory (/ˈvɛspər, vəˈsɛpər/ VESP-ər,410 və-SEP-ər, is a model used in chemistry to predict the geometry of individual molecules from the number of electron pairs surrounding their central atoms. It is also named the Gillespie-Nyholm theory after its two main developers, Ronald Gillespie and Ronald Nyholm. The premise of VSEPR is that the valence electron pairs surrounding an atom tend to repel each other and will, therefore, adopt an arrangement that minimizes this repulsion. This in turn decreases the molecule's energy and increases its stability, which determines the molecular geometry. Gillespie has emphasized that the electron-electron repulsion due to the Pauli exclusion principle is more important in determining molecular geometry than the electrostatic repulsion.