MasteringChemistry: Post-Lecture Homework Chapter 08 - Google Chrome https://ses
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MasteringChemistry: Post-Lecture Homework Chapter 08 - Google Chrome https://session.masteringchemistry.com/myct/itemView?assignmentProblemID-58201424 Chem 1210 Section 401 Signed in as Amber Plante Help Close ± Dipole Moment and Percent Ionic Character Resources 1 of 21 next » Dipole Moment and Percent Ionic Character Submit Hints My Answers Give Up Review Part Learning Goal Correct To understand the continuous range of bonding types, from purely covalent to mostly Significant Figures Feedback: Your answer 6.37-10 30 6.37x10-30 C.m was either rounded differently or used a different number of significant figures than required for this part lonic bonds, which are characterized by a complete transfer of electrons from one atom to another, are said to have 100% ionic character (Note that, in reality, there are no bonds that are 100% ionic in character because of the proximity of the bonded atoms. Even CsI , with a relatively large distance of 3.37 A , is still only about 75% ionic.) Part B The distance between the atoms of H-F is 0.92 Å. What is the distance in meters? In contrast, the electrons in a nonpolar covalent bond are shared equally between two atoms. Therefore, nonpolar covalent bonds have 0% ionic character (100% covalent character) Express your answer in meters to three significant figures r= 9.20×10-11 m Polar covalent bonds, which result from unequal sharing of electrons between the bonded atoms, are neither purely ionic nor purely covalent in character Submit Hints My Answers Give Up Review Part The dipole moment for a bond is a measure of the magnitude of polarity (how polar the bond is). Dipole moments can be used to calculate percent ionic character Correct The dipole moment is symbolized by (Greek lowercase "mu") and is equal to the charge, Q, of the atoms (measured in Coulombs, C) times the distance, r, of separation between the atoms (measured in meters, m) Part C What is the charge associated with each side of the HF molecule? Express your answer in Coulombs to three significant figures. Therefore, the units of dipole moment are Coulomb-meters, C m.Another unit of dipole moment is the debeye, D 1 D-3.34 × 10 30 C-m The percent ionic character is calculated by dividing the charge, Q, by the charge on a single electron, 1.60 × 10 19 C 20 6.61 10 Submit Give Up Review Part Incorrect; Try Again; 4 attempts remaining Not quite. Check through your calculations, you may have made a rounding error or used the wrong number of significant figures. Part D What is the percent ionic character of the H-F bond? Express your answer numerically to three significant figures 41.5 Submit Give Up Review Part Incorrect; Try Again; 5 attempts remaining Not quite. Check through your calculations; you may have made a rounding error or used the wrong number of significant figures. 4:12 AM ContinueExplanation / Answer
c) 6.93 x 10-20 C
dipole moment = Q x r
From a, dipole moment = 6.37 x 10-30 C.m
From b, r = 9.2 x 10-11 m
Then
Q = dipole moment/ r = 6.37 x 10-30 C.m / 9.2 x 10-11 m = 6.93 x 10-20 C
d) 43.25 %
% ionic charge = charge / charge on sinngle electron x 100
= 6.93 x 10-20 C / 1.602 x 10-19 C x 100
= 43.25 %