Chemistry Bonding
Assessment
1) Describe the difference between ionic and covalent bond. Ionic bonds have electrostatic forces that hold cations and anions together, and are electronic neutral. Covalent bonds are bonds that don’t give or take any electrons. In stead they share the elctrons
50) Which of these compounds contain elements that do not follow the octet rule? Explain. a) NF3: 5 + (7*3) = 26
b) PCl2F3: 5 + (7*2) + (7*3) = 40
c) SF4: 6 + (7 *4) = 24
d) SCl2: 6 + (7*2) = 20 The answer is “d” because it does not have eight valence electrons.
64) Explain why each electron structure is incorrect. Replace each structure with one that is more acceptable.
a)
It is incorrect because neither of the atoms follow the octet rule and doesn’t add up to a correct charge. They don’t have any bonds either.
b)
The Lewis dot structure doesn’t follow the octet rule, have the correct number of electrons, or any bonds.
74) Ethyl alcohol and dimethyl ether each have to same molecular formula, C2H6O. Ethyl alcohol has a much higher boiling point (78°C) than dimethyl ether (-25°C). Propose an explanation for this difference. Ether molecules cannot form hydrogen bonds with each other and therefor result in a much lower boiling point than alcohols.
76) Is this statement true or false? “As the electronegativity difference between covalently bonded atoms increases, the strength of the bond increases.” There is no particular pattern between electronegativity difference and bond strength.
Standardized Test Prep
1) A bond in which two atoms share a pair of electrons is not:
c) an ionic bond
2) How many valence electrons are in a molecule of phosphoric acid, H3PO4?
d) 32
3) Which of these molecules can form a hydrogen bond with a water molecule?
c) O2
4) Which substance contains both covalent and ionic bonds?
d) CaCl2
5) Which of these bonds is most popular?
c) H-F
6) Draw the electron dot structure for CH4, NCl3, H2S,
1) Describe the difference between ionic and covalent bond. Ionic bonds have electrostatic forces that hold cations and anions together, and are electronic neutral. Covalent bonds are bonds that don’t give or take any electrons. In stead they share the elctrons
50) Which of these compounds contain elements that do not follow the octet rule? Explain. a) NF3: 5 + (7*3) = 26
b) PCl2F3: 5 + (7*2) + (7*3) = 40
c) SF4: 6 + (7 *4) = 24
d) SCl2: 6 + (7*2) = 20 The answer is “d” because it does not have eight valence electrons.
64) Explain why each electron structure is incorrect. Replace each structure with one that is more acceptable.
a)
It is incorrect because neither of the atoms follow the octet rule and doesn’t add up to a correct charge. They don’t have any bonds either.
b)
The Lewis dot structure doesn’t follow the octet rule, have the correct number of electrons, or any bonds.
74) Ethyl alcohol and dimethyl ether each have to same molecular formula, C2H6O. Ethyl alcohol has a much higher boiling point (78°C) than dimethyl ether (-25°C). Propose an explanation for this difference. Ether molecules cannot form hydrogen bonds with each other and therefor result in a much lower boiling point than alcohols.
76) Is this statement true or false? “As the electronegativity difference between covalently bonded atoms increases, the strength of the bond increases.” There is no particular pattern between electronegativity difference and bond strength.
Standardized Test Prep
1) A bond in which two atoms share a pair of electrons is not:
c) an ionic bond
2) How many valence electrons are in a molecule of phosphoric acid, H3PO4?
d) 32
3) Which of these molecules can form a hydrogen bond with a water molecule?
c) O2
4) Which substance contains both covalent and ionic bonds?
d) CaCl2
5) Which of these bonds is most popular?
c) H-F
6) Draw the electron dot structure for CH4, NCl3, H2S,