Chemistry: The Central Science, 10th edition Theodore L. Brown, H. Eugene LeMay, Jr., and Bruce E. Bursten Chapter 8 Basic Concepts of Chemical Bonding Todd Austell, The University of North Carolina 2006, Pearson Prentice Hall 1. - 2. - 3. - 4. - 1. - 2. - 3. - 4. - 1. 2. 3. 4. Each magnesium atom loses one electron and each fluorine atom gains two electrons. Each magnesium atom loses two electrons and each fluorine atom gains one electron. Each magnesium atom gains one electron and each fluorine atom loses two electrons. Each magnesium atom gains two electrons and each fluorine atom loses one electron. 1. 2. 3. 4. Each magnesium atom loses one electron and each fluorine atom gains two electrons. Each magnesium atom loses two electrons and each fluorine atom gains one electron. Each magnesium atom gains one electron and each fluorine atom loses two electrons. Each magnesium atom gains two electrons and each fluorine atom loses one electron. 1. 2. 3. 4. Rh Tc Ru Pd 1. 2. 3. 4. Rh Tc Ru Pd 1. 2. 3. 4. There are no attractive forces in He2; that’s why it doesn’t exist. Attractive forces are between between the two entire atoms; repulsive forces are only between the electron clouds. Attractive forces are between each electron and either nucleus; repulsive forces are those between the two nuclei and those between the two electrons. Attractive forces are between each atom’s two electrons and between the two nuclei; repulsive forces are those between the nuclei and the two electrons. 1. 2. 3. 4. There are no attractive forces in He2; that’s why it doesn’t exist. Attractive forces are between between the two entire atoms; repulsive forces are only between the electron clouds. Attractive forces are between each electron and either nucleus; repulsive forces are those between the two nuclei and those between the two electrons. Attractive forces are between each atom’s two electrons and between the two nuclei; repulsive forces are those between the nuclei and the two electrons. 1. 2. 3. The repulsive forces are greater than the attractive forces. The attractive and repulsive forces are equal and thus balance each other out. The attractive forces are greater than the repulsive forces. 1. 2. 3. The repulsive forces are greater than the attractive forces. The attractive and repulsive forces are equal and thus balance each other out. The attractive forces are greater than the repulsive forces. 1. 2. 3. C–O in carbon monoxide is a single bond. C–O in carbon monoxide is a double bond. C–O in carbon monoxide is a triple bond. 1. 2. 3. C–O in carbon monoxide is a single bond. C–O in carbon monoxide is a double bond. C–O in carbon monoxide is a triple bond. 1. 2. 3. 4. EN and EA are the same; they both measure the same characteristic. EA measures the energy released when an isolated atom gains an electron to form a 1– ion; EN measures the ability of an atom to hold onto its own electrons and attract electrons from other atoms. EN values of neutral atoms are just the negative of EA values of neutral atoms. EN measures the energy released when an isolated atom gains an electron to form a 1– ion; EA measures the ability of an atom to hold onto its own electrons and attract electrons from other atoms. 1. 2. 3. 4. EN and EA are the same; they both measure the same characteristic. EA measures the energy released when an isolated atom gains an electron to form a 1– ion; EN measures the ability of an atom to hold onto its own electrons and attract electrons from other atoms. EN values of neutral atoms are just the negative of EA values of neutral atoms. EN measures the energy released when an isolated atom gains an electron to form a 1– ion; EA measures the ability of an atom to hold onto its own electrons and attract electrons from other atoms. 1. 2. 3. nonpolar polar covalent ionic 1. 2. 3. nonpolar polar covalent ionic 1. 2. 3. 4. ClF IF They have the same dipole moment. Neither has a dipole moment; they are both nonpolar. 1. 2. 3. 4. ClF IF They have the same dipole moment. Neither has a dipole moment; they are both nonpolar. 1. 2. 3. 4. The large size of the I and the Br make the charge density less noticeable. The dipole moments in both HI and HBr are in the opposite direction of HF and HCl. Because HI and HBr are both strong acids, less negative charge forms on the halogens. In HI and HBr the electronegativity differences are too small to lead to large charge separations in the molecules. 1. 2. 3. 4. The large size of the I and the Br make the charge density less noticeable. The dipole moments in both HI and HBr are in the opposite direction of HF and HCl. Because HI and HBr are both strong acids, less negative charge forms on the halogens. In HI and HBr the electronegativity differences are too small to lead to large charge separations in the molecules. 1. 2. 3. OsO4 MoO3 Both compounds have the same melting point. 1. 2. 3. OsO4 MoO3 Both compounds have the same melting point. 1. 2. 3. 4. The structure actually represents an ion. The F in the structure must have four covalent bonds attached to it. There must be another F in the structure carrying a –1 formal charge. There must be a better Lewis structure since F is not expected to carry a formal charge of +1, being the most electronegative element. 1. 2. 3. 4. The structure actually represents an ion. The F in the structure must have four covalent bonds attached to it. There must be another F in the structure carrying a –1 formal charge. There must be a better Lewis structure since F is not expected to carry a formal charge of +1, being the most electronegative element. 1. 2. Yes No 1. 2. Yes No 1. 2. 3. 4. one-and-a-fifth bonds one-and-a-forth bonds one-and-a-third bonds one-and-a-half bonds 1. 2. 3. 4. one-and-a-fifth bonds one-and-a-forth bonds one-and-a-third bonds one-and-a-half bonds 1. 2. Yes, because double bonds can be moved to give equivalent structures. No, because double bonds cannot be moved to give equivalent structures due to fixed hydrogens. 1. 2. Yes, because double bonds can be moved to give equivalent structures. No, because double bonds cannot be moved to give equivalent structures due to fixed hydrogens. 1. The enthalpy of atomization / 7 bonds broken = a good estimate of D(CC). 2. The enthalpy of atomization – 6 · D(CH) = a good estimate of D(CC). 3. The enthalpy of atomization + 6 · D(CH) = a good estimate of D(CC). The enthalpy of atomization / 7 bonds broken – 6D(CH) = a good estimate of D(CC). 4. 1. The enthalpy of atomization / 7 bonds broken = a good estimate of D(CC). 2. The enthalpy of atomization – 6 · D(CH) = a good estimate of D(CC). 3. The enthalpy of atomization + 6 · D(CH) = a good estimate of D(CC). The enthalpy of atomization / 7 bonds broken – 6D(CH) = a good estimate of D(CC). 4.