Study with the several resources on Docsity
Earn points by helping other students or get them with a premium plan
Prepare for your exams
Study with the several resources on Docsity
Earn points to download
Earn points by helping other students or get them with a premium plan
Community
Ask the community for help and clear up your study doubts
Discover the best universities in your country according to Docsity users
Free resources
Download our free guides on studying techniques, anxiety management strategies, and thesis advice from Docsity tutors
Rules for determining oxidation numbers of elements in compounds and ions, as well as an introduction to ionic bonding. It covers topics such as free elements, the sum of oxidation numbers in compounds and ions, the oxidation numbers of specific elements, and electron density distribution. It also introduces polar and nonpolar covalent bonds, and the concept of dipole moments.
Typology: Lecture notes
1 / 33
This page cannot be seen from the preview
Don't miss anything!
The oxidation number of hydrogen is +1when it is combined with moreelectronegative elements (most nonmetals)and –1 when it is combined with moreelectropositive elements (metals)
The oxidation number of Group 1A elementsis always +1 and the oxidation number ofGroup 2A elements is always +
The oxidation number of oxygen inmost compounds is –
Oxidation numbers for other elements areusually determined by the number ofelectrons they need to gain or lose to attainthe electron configuration of a noble gas
This bond is called a nonpolar covalent bond It is characterized by the symmetricalcharge distribution
F is more electronegative than H In this molecule the electron pairwill be shifted towards the F atom This bond is called a polar covalent bond The charge distribution is not symmetrical
Polar molecules can be attracted bymagnetic and electric fields We sometimes represent thesemolecules as dipoles The direction of the dipole is fromthe positive to the negative pole Each dipole is characterized by adipole moment The larger the difference in theelectronegativities of the bondedelements, the higher the dipolemoment of the molecule
All bonds have some ionic and somecovalent character For example, HI is about17% ionic and 83% covalent As the electronegativity differenceincreases, the bond becomes more polar less covalent more ionic The Continuous Rangeof Bonding Types
Which of these bonds is more polar:^
Cl Na
Na
Br
Which of these bonds hasthe highest dipole moment:^
In most of their compounds,the representative elementsachieve noble gas configurations Lewis dot formulas are based onthe octet rule Electrons which are shared amongtwo atoms are called bondingelectrons Unshared electrons are calledlone pairs or nonbonding electrons
Lewis formulas can also bedrawn for polyatomic ions
Covalent bonds are formedwhen atoms share electrons If the atoms share 2 electronsa single covalent bond is formed If the atoms share 4 electronsa double covalent bond is formed If the atoms share 6 electronsa triple covalent bond is formed
