2.
The shortest bond would be present in which of the following substance?
Explanation
All the bonds except in CO are single bonds. The CO bond is a triple bond. Triple bonds are shorter than double bonds, which are shorter than single bonds. Drawing Lewis structures might help you answer this question
3.
Which of the following does not have one or more bonds?
Explanation
Answers B through D contain molecules or ions with double or triple bonds. Double and triple bonds contain pi bonds. Water has only single (sigma) bonds. If any of these are not obvious to you, draw a Lewis structure.
4.
Which of the following is polar?
Explanation
The VSEPR model predicts all the other molecules to be nonpolar.
5.
Resonance structures are necessary to describe the bonding in which of the following?H2O
Explanation
All the other answers involve species contain only single bonds. Substances without double or triple bonds seldom need resonance structures.
6.
An explanation of the equivalent bond lengths of the nitrite ion is:
Correct Answer
A. Resonance structures
Explanation
Resonance causes bonds to have the same average length.
7.
Most organic substances have low melting points. This may be because, in most cases, the intermolecular forces are:
Correct Answer
A. Van der Waals attractions
Explanation
Many organic molecules are non polar,. Nonpolar substances are held together by weak van der Waals attractions.
8.
Which of the following has more than one unshared pair of valence electrons on the central atom?
Explanation
fLewis structures are requires. You do not need to draw all of them. A and B have one unshared pair, while C does not have an unshared pair. D has two unshared pairs
9.
What is the expected hybridization of the central atom in a molecule of TiCl4? This molecule is tetrahedral.
Explanation
Tetrahedral molecules are normally spy hybridized.
10.
The only substance listed below that contains ionc, sigma, and pi bonds is:
Explanation
Only A and D are ionic. The chloride ion has no internal bonds, so sigma and pi are not possible.
11.
The electron pairs point toard the corners of which geometrical shape for a molecule with spy hybrid orbitals?
Correct Answer
A. Trigonal planar
Explanation
This hybridization requires a geometrical shape with three corners.
12.
Regular tetrahedral molecules or ions include which of the following?
Explanation
One or more Lewis structures may help you. A is an irregular tetrahedron (seesaw); C and D are square planar.
13.
Which molecule or ion in the following list has the greatest number of unshared electrons around the central atom?
Explanation
A has 0. B has 2. C and D have 0. You may need to draw one or more Lewis structures.
14.
Which of the following molecules is the most polar?
Explanation
Drawing one or more Lewis structures may help you. Only A and C are polar. Only the ammonia has hydrogen bonding, which is very, very polar.
15.
Which of the following molecules is the least polar?
Explanation
All the molecules are polar except B.
16.
Which of the following processes involves breaking an ionic bond?
Correct Answer
A. 2KBr(s) --> 2K(g) + Br2(g)
Explanation
C is breaking metallic bonding. All the others involve covalently bonded molecules.
17.
Compounds are ___ substances that have a fixed proportion of elements.
Correct Answer
Pure
Explanation
Compounds are pure substances that have a fixed proportion of elements. This means that compounds are made up of two or more different elements that are chemically bonded together in a specific ratio. The elements in a compound cannot be separated by physical means and they exist in a fixed proportion by mass. Therefore, compounds are considered pure substances because they have a definite composition and properties that are different from the elements they are made of.
18.
____ react with ____ to form ionic bonds, and ____ react with other ____ to form covalent bonds.
Correct Answer
Metals, nonmetals, nonmetals, nonmetals
Explanation
Metals tend to lose electrons and nonmetals tend to gain electrons. When metals react with nonmetals, the metal atoms lose electrons and become positively charged ions, while the nonmetal atoms gain electrons and become negatively charged ions. These oppositely charged ions attract each other and form ionic bonds. On the other hand, when nonmetals react with other nonmetals, they share electrons to achieve a stable electron configuration. This sharing of electrons between nonmetal atoms results in the formation of covalent bonds. Therefore, the given answer correctly identifies the types of elements that react to form ionic and covalent bonds.
19.
Please fill answer below
Correct Answer
N/A
20.
The Lewis electron-dot structure is a way of representing an element and its valence electrons.
Explanation
The Lewis electron-dot structure is indeed a way of representing an element and its valence electrons. This structure uses dots to represent the valence electrons around the symbol of the element. It helps in understanding the bonding and electron distribution in molecules and ions. Therefore, the statement is true.
21.
Atoms tend to ____, ____, or ____ electrons to achieve the same electronic configuration as the nearest noble gas.
Correct Answer
lose, gain, share
Explanation
Atoms tend to lose, gain, or share electrons to achieve the same electronic configuration as the nearest noble gas. This is because noble gases have a stable electronic configuration, with a full outer shell of electrons. By losing, gaining, or sharing electrons, atoms can either gain a full outer shell or achieve a stable electron configuration similar to that of a noble gas. This process allows atoms to become more stable and lower their energy levels.
22.
Atoms are generally the least stable when they have a complete octet (eight electrons).
Explanation
Most stable, not least stable.
23.
Ionic bonds result when a metal loses electrons to form ____ and a nonmetal gains those electrons to form an ____.
Correct Answer
Cation, Anion
Explanation
Ionic bonds occur when a metal atom loses electrons and becomes a positively charged ion, known as a cation. At the same time, a nonmetal atom gains those electrons and becomes a negatively charged ion, known as an anion. The attraction between the oppositely charged ions leads to the formation of an ionic bond.
24.
Ionic bonds can also result from the interaction of polyatomic ions.
Explanation
Ionic bonds can form between polyatomic ions because polyatomic ions are charged particles that have gained or lost electrons. These charged ions are attracted to ions of opposite charge, leading to the formation of ionic bonds. This is why it is true that ionic bonds can result from the interaction of polyatomic ions.
25.
The attraction of the opposite charges (anions and cations) forms the ____ bonds.
Correct Answer
Ionic
Explanation
The attraction between opposite charges, specifically anions and cations, forms ionic bonds. In an ionic bond, electrons are transferred from one atom to another, resulting in the formation of positively charged cations and negatively charged anions. These charged particles are then attracted to each other, creating a strong bond. Ionic bonds are typically found in compounds composed of metals and nonmetals, such as sodium chloride (NaCl), where the sodium cation is attracted to the chloride anion.
26.
In covalent bonding, two atoms ____ one or more electron pairs
Correct Answer
Share
Explanation
In covalent bonding, two atoms share one or more electron pairs. Covalent bonding occurs when atoms have similar electronegativity and they share electrons to achieve a stable electron configuration. By sharing electrons, both atoms can fill their outermost energy levels and become more stable. This type of bonding is typically found between nonmetal atoms.
27.
If the electrons are not shared equally, the bond is a non polar covalent bond, but unequal sharing to its electronegativity.
Explanation
If they are shared equally, not if they are not shared equally.
28.
The element that will have the greatest attraction for a bonding pair electrons is related to its ____.
Correct Answer
Electronegativity
Explanation
Electronegativity is a measure of an atom's ability to attract a bonding pair of electrons towards itself in a chemical bond. The higher the electronegativity of an element, the greater its attraction for the bonding pair of electrons. Therefore, the element with the highest electronegativity will have the greatest attraction for a bonding pair of electrons.
29.
Electronegativity values increase from ____ to ____ on the periodic table and decrease from ____ to ____.
Correct Answer
Left, right, top, bottom
Explanation
Electronegativity values increase from left to right on the periodic table because as you move across a period, the number of protons in the nucleus increases, resulting in a stronger attraction for electrons. Electronegativity values also increase from bottom to top on the periodic table because as you move up a group, the atomic size decreases and the effective nuclear charge increases, leading to a stronger pull on electrons.
30.
Molecular geometry, the arrangement of atoms in 3D space, cannot be predicted using the VSEPR theory. This theory says the electron pairs around a central atom will not try to get as far as possible from each other to minimize the repulsive forces.
Explanation
they can be predicted, they will try to get as far as possible from each other
31.
The valence bond theory describes ____ bonding as the overlap of atomic orbitals to form a new kind of orbital, a hybrid orbital.
Correct Answer
Covalent
Explanation
The valence bond theory describes covalent bonding as the overlap of atomic orbitals to form a new kind of orbital, a hybrid orbital. In covalent bonding, two atoms share electrons, resulting in the formation of a strong bond between them. This sharing of electrons occurs when the atomic orbitals of the atoms overlap, creating a hybrid orbital that is a combination of the original atomic orbitals. This hybrid orbital allows for the formation of a stable covalent bond between the atoms.
32.
The number of hybrid orbitals is the same as the number of atomic orbitals that were mixed together.
Explanation
The statement is true because when atomic orbitals combine to form hybrid orbitals, the number of hybrid orbitals formed is equal to the number of atomic orbitals that were mixed together. This is based on the concept of hybridization, where atomic orbitals of similar energy levels combine to form new orbitals with different shapes and orientations. The resulting hybrid orbitals are used to explain the bonding in molecules and determine their molecular geometry.
33.
In the valence bond theory, ____ bonds overlap n a line drawn between the two nuclei, while pi bonds result from the overlap of atomic orbitals above and below a line connecting the two atomic nuclei.
Correct Answer
Sigma
Explanation
In the valence bond theory, sigma bonds are formed when atomic orbitals overlap along a line connecting the two atomic nuclei. This type of overlap allows for the maximum electron density between the nuclei, resulting in a strong bond. On the other hand, pi bonds are formed from the overlap of atomic orbitals above and below the line connecting the two atomic nuclei. This type of overlap creates a region of electron density above and below the sigma bond, resulting in a weaker bond. Therefore, sigma bonds overlap in a line between the nuclei, while pi bonds result from the overlap above and below this line.
34.
A double or triple bond is always composed of one sigma bond and the rest pi bonds.
Explanation
A double or triple bond is formed when two or three pairs of electrons are shared between two atoms. In a double bond, one pair of electrons is shared through a sigma bond, which is a strong, direct overlap of atomic orbitals. The remaining pairs of electrons are shared through pi bonds, which are formed by the sideways overlap of p orbitals. Similarly, in a triple bond, one pair of electrons is shared through a sigma bond, and the remaining two pairs of electrons are shared through pi bonds. Therefore, it is true that a double or triple bond is always composed of one sigma bond and the rest pi bonds.
35.
____ occurs when more than one Lewis structures can be written for a molecule. The actual structure of the molecule is an average of the Lewis resonance structures.
Correct Answer
Resonance
Explanation
Resonance occurs when more than one Lewis structure can be written for a molecule. This means that there are multiple ways to arrange the electrons in the molecule, resulting in different possible structures. However, the actual structure of the molecule is not represented by any single Lewis structure, but rather is an average of all the possible resonance structures. This concept is important in understanding the bonding and reactivity of molecules.
36.
The lower the bond order, the shorter and stronger the bond.
Explanation
The higher the bond order, not lower