chemistry 121 / chem 121 exam 4 questions and answers
Exam Page 1
Show the determination of the charge on the ion formed by the Ga31 atom.
Ga31 (nonmetal = gain electrons) 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p1 lose 4 → Ga+3
Answer Key
Show the determination of the charge on the ion formed by the Ga31 atom.
Ga31 (metal = lose electrons) 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p1
lose 3e → Ga+3
Exam Page 2
Using the electronegativities from the table in the help files found by clicking on upper right of this
exam page, show the determination of the polarity of each different type of bond in the following
molecule:
H- O bond electronegativity difference = 3.5 - 2.1 = 1.4 1.6 - 0.5 bond is Polar
N = O bond electronegativity difference = 3.5 - 3.0 = 0.5 1.6 - 0.5 bond is Polar
Answer Key
Using the electronegativities from the table in the help files found by clicking on upper right of this
exam page, show the determination of the polarity of each different type of bond in the following
molecule:
H-O bond electronegativity difference = 3.5 - 2.1 = 1.4
1.6 - 0.5 bond is Polar
This study source was downloaded by 100000849317663 from CourseHero.com on 07-09-2022 19:03:52 GMT -05:00
https://www.coursehero.com/file/50777005/Exam-4docx/
, N-O bond electronegativity difference = 3.5 - 3.0 = 0.5
1.6 - 0.5 bond is Polar
Exam Page 5
Determine the electron geometry and explain your answer for the Si atom in SiH4.
4 groups of electrons around Si = Tetrahedral Electron Geometry
Tetrahedral electron geometry = sp3 Hybridization of Si
4 atoms around central Tetrahedral atom = Tetrahedral Shape
Si-H bond (2.1 - 1.8) is nonpolar = all nonpolarbonds = Nonpolar molecular polarity
Answer Key
Determine the electron geometry and explain your answer for the Si atom in SiH4.
The Si atom in SiH4 has 4 groups of electrons around it in its Lewis structure, therefore, its
electron geometry would be tetrahedral.
Exam Page 6
Determine the hybridization and explain your answer for the C atom in HCN.
2 groups of electrons around C = Linear Electron Geometry
Linear Electron Geometry = sp Hybridization of C
2 atoms around central Linear atom = Linear shape
CH bond (2.5 - 2.1) is nonpolar
C≡N bond (3.0 - 2.5) is polar = at least one polar bonds = Polar molecular polarity
Answer Key
Determine the hybridization and explain your answer for the C atom in HCN.
This study source was downloaded by 100000849317663 from CourseHero.com on 07-09-2022 19:03:52 GMT -05:00
https://www.coursehero.com/file/50777005/Exam-4docx/
Exam Page 1
Show the determination of the charge on the ion formed by the Ga31 atom.
Ga31 (nonmetal = gain electrons) 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p1 lose 4 → Ga+3
Answer Key
Show the determination of the charge on the ion formed by the Ga31 atom.
Ga31 (metal = lose electrons) 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p1
lose 3e → Ga+3
Exam Page 2
Using the electronegativities from the table in the help files found by clicking on upper right of this
exam page, show the determination of the polarity of each different type of bond in the following
molecule:
H- O bond electronegativity difference = 3.5 - 2.1 = 1.4 1.6 - 0.5 bond is Polar
N = O bond electronegativity difference = 3.5 - 3.0 = 0.5 1.6 - 0.5 bond is Polar
Answer Key
Using the electronegativities from the table in the help files found by clicking on upper right of this
exam page, show the determination of the polarity of each different type of bond in the following
molecule:
H-O bond electronegativity difference = 3.5 - 2.1 = 1.4
1.6 - 0.5 bond is Polar
This study source was downloaded by 100000849317663 from CourseHero.com on 07-09-2022 19:03:52 GMT -05:00
https://www.coursehero.com/file/50777005/Exam-4docx/
, N-O bond electronegativity difference = 3.5 - 3.0 = 0.5
1.6 - 0.5 bond is Polar
Exam Page 5
Determine the electron geometry and explain your answer for the Si atom in SiH4.
4 groups of electrons around Si = Tetrahedral Electron Geometry
Tetrahedral electron geometry = sp3 Hybridization of Si
4 atoms around central Tetrahedral atom = Tetrahedral Shape
Si-H bond (2.1 - 1.8) is nonpolar = all nonpolarbonds = Nonpolar molecular polarity
Answer Key
Determine the electron geometry and explain your answer for the Si atom in SiH4.
The Si atom in SiH4 has 4 groups of electrons around it in its Lewis structure, therefore, its
electron geometry would be tetrahedral.
Exam Page 6
Determine the hybridization and explain your answer for the C atom in HCN.
2 groups of electrons around C = Linear Electron Geometry
Linear Electron Geometry = sp Hybridization of C
2 atoms around central Linear atom = Linear shape
CH bond (2.5 - 2.1) is nonpolar
C≡N bond (3.0 - 2.5) is polar = at least one polar bonds = Polar molecular polarity
Answer Key
Determine the hybridization and explain your answer for the C atom in HCN.
This study source was downloaded by 100000849317663 from CourseHero.com on 07-09-2022 19:03:52 GMT -05:00
https://www.coursehero.com/file/50777005/Exam-4docx/
