Difference in electronegativity and the electron is

Info icon This preview shows pages 15–18. Sign up to view the full content.

View Full Document Right Arrow Icon
difference in electronegativity and the electron is almost completely transferred to the nonmetal, and the bond is ionic e.g. NaCl if there is an intermediate electronegativity difference such as between two nonmetals, then the bond is polar covalent e.g. HCl
Image of page 15

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
we can quantify the polarity of a bond by the size of its dipole moment a occurs when there's a separation of positive and negative charge the magnitude of a dipole moment created by separating two particles of equal but opposite charge of magnitude q by a distance of r is given by: the debye (D) is the common unit for a dipole moment the percent ionic character is defined as the ratio of a bond's actual dipole moment to the dipole moment it would have if the electron were completely transferred from one atom to another, multiplied by 100% a bond with complete transfer of an electron is known to have 100% ionic character (even the most ionic bonds do not reach this ideal) as expected as electronegativity difference increases so does the percent ionic character , no bond is 100% ionic so any bond with greater than 50% ionic character is referred to as an ionic bond How to write a lewis structure: 1. write the correct skeletal formula for the structure the atoms must be in the same positions that they would be in nature e.g. for water, HHO would be incorrect, HOH would be correct hydrogen atoms are always terminal - on the end of the molecule central atoms must always have at least two bonds, which is why hydrogen is never a central atom always put the more electronegative atoms on the terminal ends use formal charge to determine between competing Lewis structures 2. determine the total number of electrons for the Lewis structure by summing the valence
Image of page 16
electrons of each atom in the molecule number of valence electrons for main group elements is its group number when writing Lewis structures for molecules containing polyatomic ions, remember to take this into consideration when determining the total number of electrons - add one electron for every negative charge, and remove one electron for every positive charge the atom that loses/gains an electron is not important, only the total number of electrons is important 3. distribute electrons among the atoms, giving octects (or duets for hydrogen) to as many atoms as possible, if single bonds don't fulfill obtaining an octet, use double or triple bonds Resonance occurs when there are two or more valid Lewis structures for the same molecule in nature the molecule tends to exist as an average of the two possible Lewis structures e.g. O3 has two possible resonance structures each containing one single bond and one double bond yet we find that, in nature, both bonds are intermediate between single and double bonds, both in length and in strength to account for these different representations of the same molecule we draw all possible types of Lewis structures with double-headed arrows between them - known as
Image of page 17

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Image of page 18
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern