1. Chemistry

2.  Without bonding the universe would be a mass of individual atoms.  The type of bond defines the properties of a substance.  NaCl…shape  H 2 O and oil…dissolving

3.  Ability of atoms within a molecule to attract electrons

4.  Describes molecules with an unequal distribution of electrons  (nonpolar = equal)

5.  Describes a bond where electrons are shared

6.  Describes a bond where electrons are transferred

7.  Calculate the difference in electronegativities: > 1.7 = ionic (electrons transfer) 0.3-1.7 = polar covalent (electrons are shared unequally) <0.3 = nonpolar covalent (equal sharing of electrons)

8. a) Calculate the difference in electronegativities: 2.2 – 2.2 = 0  nonpolar covalent (equal sharing) b) Draw the electron dot/Lewis structure: H + H = H H [recall the “duet rule”—H wants 2 e - ]

9.  Describes a bond where electrons are shared equally  Less than 0.3 electronegativity difference.  Let’s look at an animation of this with H 2 : (http://web.jjay.cuny.edu/~acarpi/NSC/5-bonds.htm)http://web.jjay.cuny.edu/~acarpi/NSC/5-bonds.htm (http://www2.gasou.edu/chemdept/general/mo lecule/polar.htm)http://www2.gasou.edu/chemdept/general/mo lecule/polar.htm H 2 EN=0

10. a) calculate the difference in electronegativities: 3.5 – 2.2 = 1.3  polar covalent (unequal sharing) b) Draw the electron dot/Lewis structure: H + H + O = H O H [recall the “duet rule”—H wants 2 e - ]

11.  Describes a bond where electrons are shared unequally  Electronegativity (EN) difference is between 0.3 and 1.7.  Let’s look at an animation of this with H 2 O and HBr: (http://web.jjay.cuny.edu/~acarpi/NSC/5-bonds.htm)http://web.jjay.cuny.edu/~acarpi/NSC/5-bonds.htm (http://www2.gasou.edu/chemdept/general/mo lecule/polar.htm)http://www2.gasou.edu/chemdept/general/mo lecule/polar.htm HBr END=0.7 H 2 O END=1.4

12. a) calculate the difference in electronegativities: 4.0 – 2.2 = 1.8  ionic (electrons are transferred) b) Draw the electron dot/Lewis structure: H + F = H F + -

13.  Describes a bond where electrons are transferred.  Greater than 1.7 electronegativity difference.  Let’s look at an example of this with NaCl: (http://web.jjay.cuny.edu/~acarpi/NSC/5-bonds.htm)http://web.jjay.cuny.edu/~acarpi/NSC/5-bonds.htm (http://www2.gasou.edu/chemdept/general/mo lecule/polar.htm)http://www2.gasou.edu/chemdept/general/mo lecule/polar.htm NaCl EN =2.1