CH.5 Formal charge & CH. 6 Types of Chemical Bonds Flashcards
(18 cards)
Which of the following compounds would form the strongest ionic bond?
A. NaCl
B. KCl
C. MgCl₂
D. CaCl₂
C. MgCl₂
Ionic bond strength increases with higher ionic charge. Mg²⁺ has a +2 charge compared to Na⁺ and K⁺ (+1).
What is the formal charge of the carbon in the compound below?
-2
-1
0
+1
+2
-1
In this compound, carbon is connected to 5 electrons (rather than 4 as its group number) and thus, has a formal charge of -1. Note that when an element is connected to more electrons than its group number, it has a negative formal charge.
0
+1
+2
+3
+4
+1
In this compound, Nitrogen is connected to 4 electrons (rather than 5 as its group number) and thus, has a +1 formal charge. Note that when an element is connected to fewer electrons than its group number, it has an overall positive formal charge.
-2
-1
0
1
2
-1
In this compound, Boron is connected to 4 electrons (rather than 3 as its group number) and thus, has a formal charge of -1. Note that when an element is connected to more electrons than its group number it has a negative formal charge.
The most stable resonance structure is one in which _______.
has the least amount of charges
negative charges are on the most electronegative atoms
positive charges are on the least electronegative charges
all the atoms in the structure have octet
All of the above
All of the above
Given a resonance structure of sulfur dioxide (SO2) with one double bond and one single bond to sulfur, what is the formal charge on the sulfur atom in this arrangement?
-1
0
+1
+2
-2
+1
In the given resonance structure, Sulfur is connected to 5 electrons ( a double bond, a single bond, and a lone pair of electrons). Since Sulfur is in group 6, it has six valence electrons. Being connected to only 5 electrons gives sulfur +1 a formal charge.
Which of the following statements about resonance structures is incorrect?
Resonance structures differ only in the arrangement of electrons, not the positions of nuclei.
The actual structure of a molecule is a resonance hybrid, representing an average of all valid resonance structures.
All resonance structures contribute equally to the resonance hybrid.
Resonance structures with minimized formal charges are typically more stable.
A resonance structure with a negative charge on the most electronegative atom is usually more stable.
All resonance structures contribute equally to the resonance hybrid.
Consider the resonance structures of the nitrate ion (NO3−). Which of the following criteria does not contribute to the determination of the most stable resonance structure?
Minimized formal charges.
Placement of negative charge on the most electronegative atom.
Equal distribution of charges among all atoms.
The presence of incomplete octets on the central atom.
Maximizing the number of covalent bonds.
The presence of incomplete octets on the central atom.
Which pair of elements would form a nonpolar covalent bond?
A. H and Cl
B. Na and Cl
C. O and O
D. H and O
C. O and O
Which of the following represents the correct ranking of intramolecular forces from strongest to weakest?
A. Ionic > Network Covalent > Metallic > Covalent
B. Network Covalent > Metallic > Ionic > Polar Covalent
C. Network Covalent > Metallic > Ionic > Hydrogen Bond > Polar Covalent > Covalent
D. Covalent > Hydrogen Bond > Ionic > Metallic > Network Covalent
C. Network Covalent > Metallic > Ionic > Hydrogen Bond > Polar Covalent > Covalent
Which of the following has the weakest intermolecular forces?
A. HF
B. CH₄
C. NaCl
D. HCl
B. CH₄
Which of the following compounds has a polar covalent bond?
A. NaCl
B. H₂
C. H₂O
D. O₂
C. H₂O
Which is an example of a network covalent solid?
A. MgCl₂
B. SiO₂
C. Na
D. CH₄
B. SiO₂ quartz
A molecule of H₂O exhibits which intermolecular force?
A. Dipole-Dipole
B. Ion-Dipole
C. Hydrogen Bonding
D. Metallic
C. Hydrogen Bonding
A molecule of H₂O exhibits which intermolecular force?
A. Dipole-Dipole
B. Ion-Dipole
C. Hydrogen Bonding
D. Metallic
C. Hydrogen Bonding
What type of bond is found in metallic substances like copper (Cu)?
A. Ionic
B. Network Covalent
C. Sea of electrons
D. Hydrogen bond
C. Sea of electrons
Metallic bonding involves delocalized electrons shared among metal nuclei.
A molecule of F2 exhibits which intermolecular force?
A. Dipole-Dipole
B. Ion-Dipole
C. London Dispersion Forces
D. Metallic
C. London Dispersion Forces
- Ionic bonds - ION ION (strongest)
- ION- DIPOLE -POLAR AND NUETRAL
- Hydrogen bonds
- polar - DIPOLE- DIPOLE
- Non polar - Lodon or Van der Walls (weakest) all halogens are diatomic
Which elements at room temp are gases , liquid, and solid?
gases: F and Cl
Liquid Bromine
Solid: Iodine
