1 / 22

Names and Formulas of

Names and Formulas of. Ionic Compounds. Chemical Bonds . The bond is the force that holds two or more atoms together to form a molecule of a compound- two types Ionic and covalent Atom is to element as H He Fe Na Molecule is to compound H 2 O. Na +   , Cl−, Ca  ++   , S  =  H2SO4.

rodney
Download Presentation

Names and Formulas of

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Names and Formulasof Ionic Compounds

  2. Chemical Bonds • The bond is the force that holds two or more atoms together to form a molecule of a compound- two types • Ionic and covalent • Atom is to element as H He Fe Na • Molecule is to compound H2O

  3. Na+  , Cl−, Ca ++  , S = H2SO4 • Formula shown is simplest form of the molecule that is formed when ions combine

  4. Ions • Formed when atoms lose or gain valence electrons • May be + or - ions • They form a stable electron configuration of 8 outer electrons like the noble gases

  5. Cation is + charged ion; loses e- • Anion is – charged ion; gains e- • Ionic bonds form when anion and cations close to each other attract and form a geometric lattice

  6. Force of attraction must be broken to free atoms from each other- usually energy • Physical properties of ionic solids (NaCl salt) like m.p., b.p. hardness, ability to conduct electricity(melted or in solution) attest to strength of bond • Electrolyte: conducts electric current in liquid solution

  7. Atomic Radius • What happens to atoms as they lose electrons? Radius decreases • Opposite? Radius increases • What trends of atomic radius would one expect as atomic number increases? • As one moves from metals to non –metals? • As one moves up and down the table?

  8. Ionization Energy • The energy needed to overcome the attraction between the +positively charged nucleus and the -negatively charged electron • Measured in Joule • Energy required to ionize increases from left to right on pt • Alkali metals –low ionization energies- lose e- readily

  9. Noble gases have EXTREMELY high IE • rare to lose e- • remain stable • He, Ne, Ar, Kr, Xe, Rn

  10. Octet Rule • Atoms tend to lose or gain e- to finalize a full set of 8 valence electrons • This occurs in ionization • Natural occurrence • Makes compound formation possible

  11. PT right side, gain e- - ions or anionsPT left side, lose e- +ions or cations

  12. Electronegativity • Electronegativity is a number that describes the relative ability of an atom, when bonded, to attract electrons.

  13. Where are highest –neg.? • Electronegativity effects properties such as melting and boiling points of substances • Increases from left to right on PT • And decreases from top to bottom

  14. Subscripts in ionic compounds indicate ratio of cations to anions to form electrically neutral atoms H2CO3

  15. Monoatomic ions- form from one atom • -1 is the oxidation state or oxidation number

  16. Polyatomic ions are formed from 2 or more atoms-act as single unit with net charge

  17. Naming • Name of cation first followed by name of anion • NaCl Sodium chloride • Mg SO4 Magnesium sulfate

  18. Charge on cation and anion must = zero for an ionic compound to form • If charge is -1 it can only form bond with other ion +1 • If charge is -2, can form compound with +2 or two ions of +1

  19. Barium Nitrate • Ba (NO3)2 Barium is +2 Nitrate is -1.. (need 2 ions)

More Related