Chem 103 Modules 3 Exam Study Questions with Elaborate Answers Already Graded A+

Chem 103 Modules 3 Exam Study Questions with Elaborate Answers Already Graded A+ 1. Between which types of elements do covalent bonds form? - ANSWER A covalent bond usually forms between two nonmetals 2. Isoelectric - ANSWER Term used to describe tow elements having the same electronic configuration; the only difference is the number of protons 3. Describe the trends of electronegativity - ANSWER Decreases going down the table, increases from left to right 4. Octet rule - ANSWER the tendency of main group atoms to form enough bonds to obtain eight valence electrons 5. What are three exceptions to the octet rule? - ANSWER Odd electron molecules, electron-deficient molecules, and hypervalent molecules 6. Odd electron molecules (free radicals) - ANSWER have an odd number of valence electrons, and therefore, have an unpaired electron 7. Electron-deficient molecules - ANSWER have a central atom that has fewer electrons than needed for a noble gas configuration 8. Hypervalent molecules - ANSWER have a central atom that has more electrons than needed for a noble gas configuration 9. Formal charge - ANSWER the hypothetical charge of an atom in a molecule if the electrons in the bonds were redistributed even between the atoms 10. Core Electrons (stay at home Netflix) - ANSWER -Electrons in filled shells -Have limited influence on atomic properties -Generally unaltered in chemical reactions 11. Valence Electrons (Free spirit) - ANSWER -Electron in shell with largest N -Determine how an atom interacts with other atoms -Gained/Lost/Shared -Dictate how atoms react with other atoms 12. electron configuration - ANSWER whole sequence (1s2,2s2, etc.) 13. Core electron example (Ne) - ANSWER 1s2, 2s2, 2p6 14. Valence Electron example (S) - ANSWER [Ne] 3s2, 3p4 15. General Principle: - ANSWER Neutral atom (s or p block) will gain or lose enough electrons to become isoelectronic with nearest noble gas 16. Isoelectronic: - ANSWER identical electron count, configuration 17. Trigonal planar electron geometry - ANSWER three regions of electron density around a central atom (120 degrees) 18. Tetrahedral electron geometry - ANSWER four regions of electron density around a central atom (109.5 degrees) 19. Ionic bond - ANSWER An ionic bond is electrostatic attraction between oppositely charged cations in anions (metals and nonmetals) 20. How does a binary ionic compound form? - ANSWER A metal loses electrons (forming a cation) and donates them to a nonmetal which gains electrons informs in anion, the compound is held together by the force of electrostatic attraction 21. Covalent bond - ANSWER Attractive force between the nuclei of a molecule's atoms and pairs of electrons between atoms; a mutual attraction of atoms for a shared pair of electrons 22. Trigonal bipyramidal electron geometry - ANSWER five regions of electron density around a central atom (90 degrees and 120 degrees) 23. Octahedral electron geometry - ANSWER six regions of electron density around a central atom (90 degrees) 24. Molecular geometry - ANSWER the arrangement around a central atom, including only the placement of atoms - bonds only - lone pairs are present, but not considered for the shape name - derived from electron geometry 25. Greek prefix for 8 - ANSWER octa- 26. Greek prefix for 9 - ANSWER nona- 27. Greek prefix for 10 - ANSWER deca- 28. Polar molecule (or dipole) - ANSWER A molecule with a separation of charge; uneven charge distribution 29. Nonpolar molecule - ANSWER A molecule with no separation of charge; even charge distribution 30. Bond dipole moment - ANSWER the separation of charge in a bond (mew)... can be represented by a vector 31. Vector - ANSWER quantity with both a direction and a magnitude 32. Polar covalent bonds - ANSWER connect two atoms with differing electro negativities, leaving the less electronegative atom with a partial positive charge, and the more electronegative atom with a partial negative charge