Exam Questions and CORRECT Answers
ionic bonds - CORRECT ANSWER -two oppositely charged ions (2Na + Cl₂ =
2Na⁺+2Cl⁻)
metals tend to ______ electrons - CORRECT ANSWER -lose
nonmetals tend to ______ electrons - CORRECT ANSWER -gain
covalent bonds - CORRECT ANSWER -share at least one pair of electrons so both atoms
have 8 valence electrons
2 types of covalent bonds - CORRECT ANSWER -polar, nonpolar
polar covalent bond - CORRECT ANSWER -unequal sharing of electrons, difference in
electronegativity 0.5-1.6
nonpolar covalent bond - CORRECT ANSWER -electrons are shared equally,
electronegativity difference less than 0.5
ionic bond - CORRECT ANSWER -electronegativity difference greater than 1.6
number of valence electrons = - CORRECT ANSWER -element's group number
lewis structures of molecules steps - CORRECT ANSWER -1. find total # of valence
electrons
2. place least negative atom in the center (H always on outside)
3. place pair of electrons between each element