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#############################CEM
9/24/2026CEM 141 chapter 4.pdf##############################################################################
141 chapter 4.pdfCEM 141 chapter 4.pdf#############################################
CEM 141 chapter 4
=8-#electrons - ANS-Valence
=VE on free atom-#bonds to atom-non-bonded eelctrons - ANS-formal charge
are in a tug o war; bonds form because of the attractive forces between the atoms -
ANS-covalent bonds electrons...
carbon atoms with single bonds - ANS-alkanes
double bond in lewis structure - ANS-alkene
in the liquid state ions are free to move - ANS-Why does molten (liquid) sodium chloride conduct
electricity?
larger molecules; so the larger molecule has a higher mp/bp - ANS-LDFs are stronger in
LDFs are overcome when a hydrocarbon boils, covalent bonds still exist - ANS-Hydrocarbon
boils
molecule in which two of the same atoms are on the same side of a double bond (generally has
higher boiling point than trans isomer). - ANS-cis isomer
molecule with two of the same atoms in opposite sides of the double bond (normally has a lower
bp than cis). - ANS-trans isomer
NaCl is an ionic compound. It has ion-ion interactions not bonding. - ANS-How is bonding
different in an ionic substance like NaCl?
not a force; a charge; a charge the Valence electrons feel to the nucleus of an atom once we've
eliminated shielding/ blocking effects of the core electrons - ANS-Effective Nuclear charge
overlap end to end; single bonds; rotate - ANS-sigma bonds
pi bonds; do not have free rotation - ANS-double bonds
Single (sigma) bonds are formed when atomic or hybrid orbitals overlap directly between the
two nuclei (end-to-end overlap of orbitals). For example, sp3 + sp3, as shown above in C2H6.
When the bond rotates, the overlap stays the same so the bond is not broken.Double bonds
contain one sigma and one pi bond. Pi bonds are formed from the side-to-side overlap of
parallel p-orbitals and result in the overlap occurring above and below the plane of the nuclei.
######################################################################################!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!Q
CEM 141 chapter 4CEM 141 chapter 4.pdf#######################################################################
#############################CEM
9/24/2026CEM 141 chapter 4.pdf##############################################################################
141 chapter 4.pdfCEM 141 chapter 4.pdf#############################################
CEM 141 chapter 4
=8-#electrons - ANS-Valence
=VE on free atom-#bonds to atom-non-bonded eelctrons - ANS-formal charge
are in a tug o war; bonds form because of the attractive forces between the atoms -
ANS-covalent bonds electrons...
carbon atoms with single bonds - ANS-alkanes
double bond in lewis structure - ANS-alkene
in the liquid state ions are free to move - ANS-Why does molten (liquid) sodium chloride conduct
electricity?
larger molecules; so the larger molecule has a higher mp/bp - ANS-LDFs are stronger in
LDFs are overcome when a hydrocarbon boils, covalent bonds still exist - ANS-Hydrocarbon
boils
molecule in which two of the same atoms are on the same side of a double bond (generally has
higher boiling point than trans isomer). - ANS-cis isomer
molecule with two of the same atoms in opposite sides of the double bond (normally has a lower
bp than cis). - ANS-trans isomer
NaCl is an ionic compound. It has ion-ion interactions not bonding. - ANS-How is bonding
different in an ionic substance like NaCl?
not a force; a charge; a charge the Valence electrons feel to the nucleus of an atom once we've
eliminated shielding/ blocking effects of the core electrons - ANS-Effective Nuclear charge
overlap end to end; single bonds; rotate - ANS-sigma bonds
pi bonds; do not have free rotation - ANS-double bonds
Single (sigma) bonds are formed when atomic or hybrid orbitals overlap directly between the
two nuclei (end-to-end overlap of orbitals). For example, sp3 + sp3, as shown above in C2H6.
When the bond rotates, the overlap stays the same so the bond is not broken.Double bonds
contain one sigma and one pi bond. Pi bonds are formed from the side-to-side overlap of
parallel p-orbitals and result in the overlap occurring above and below the plane of the nuclei.
######################################################################################!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!Q
CEM 141 chapter 4CEM 141 chapter 4.pdf#######################################################################