Question 1

Arrange the following in order of increasing ionic character: Al₂S₃,MgS,Na₂S,P₄S₃,S₈.

Accepted Answer

The ionic character increases with the difference in electronegativity between the elements. S8 is a covalent molecule, P4S3 is mostly covalent, Al2S3 has some ionic character, MgS is more ionic, and Na2S is the most ionic due to the large difference in electronegativity between Na and S.

Question 2

When melting S₈,________ forces must be overcome and S₈ is expected to have a ________ melting point than MgS.

Accepted Answer

S8 is a molecular solid with weak intermolecular forces (van der Waals forces) that need to be overcome when melting, resulting in a lower melting point compared to the ionic compound MgS, which has strong ionic bonds.

Question 3

How many of the σ bonds in H₂SO₄ are coordinate covalent bonds?

Accepted Answer

Coordinate covalent bonds are formed where one atom donates both of the electrons in the bonding pair to the other atom. In the given molecule, there are 2 sulfur atoms (S) and 2 phosphorus atoms (P) that have a lone pair of electrons available to form coordinate covalent bonds. Each of these atoms forms a coordinate covalent bond with a boron atom (B) connected to an SO group. Therefore, there are 2 coordinate covalent bonds in the molecule.

Question 4

The nitrogen-nitrogen bond in :N  N: has a bond order of

Accepted Answer

The answer of The nitrogen-nitrogen bond in :N  N:...

Question 5

A::A represents

Accepted Answer

A::A represents a double bond.

Question 6

Which is the most acceptable electron dot structure for N₂H₂?

Accepted Answer

The answer of Which is the most acceptable electron dot...

Question 7

How many lone pairs are on the Br atom in BrI₂^-?

Accepted Answer

The Br atom in BrI2^- has 7 valence electrons. It forms two bonds with iodine atoms, using 2 electrons. The remaining 5 electrons form 2 lone pairs and 1 additional electron, which accounts for the negative charge, resulting in 3 lone pairs.

Question 8

NO₂^- is be expected to have

Accepted Answer

The string of characters suggests a repeating pattern of alternating single and double bonds (₂^{). However, the final two characters (}) indicate something different - two identical bonds that are intermediate between a single and a double bond (denoted by the "S1S1"). Therefore, the best answer is D, which corresponds to "two identical bonds intermediate between a single and a double bond."

Question 9

Elements that can accommodate more than eight electrons in their valence shell occur only in periodic table row

Accepted Answer

Elements in the third row of the periodic table and below can accommodate more than eight electrons in their valence shell due to the availability of d orbitals starting from the third period, allowing for expanded octets.

Question 10

Consider a molecule with the following connections:  When a valid electron dot structure is written,how many double bonds will the molecule contain?

Accepted Answer

The answer of Consider a molecule with the following connections:...

Question 11

In the most acceptable electron-dot structure for carbonyl fluoride,COF₂ the central atom is

Accepted Answer

In the most acceptable electron-dot structure for carbonyl fluoride (COF2), carbon (C) is the central atom and it is doubly bonded to oxygen (O). This allows for the correct distribution of electrons, fulfilling the octet rule for both carbon and oxygen.

Question 12

The electronegativities for the elements vary from 0.7 for cesium to 4.0 for fluorine.The electronegativity for iodine is 2.5.Based entirely on the general guidelines for electronegativities and bond character,

Accepted Answer

The answer of The electronegativities for the elements vary from...

Question 13

In the electron dot structure of HCN,the bond order of CN is

Accepted Answer

In the electron dot structure of HCN (hydrogen cyanide), the carbon (C) and nitrogen (N) atoms are connected by a triple bond, which corresponds to a bond order of 3. This means there are three shared pairs of electrons between the carbon and nitrogen atoms.

Question 14

How many lone pairs in the correct electron dot structure of O₃?

Accepted Answer

The answer of How many lone pairs in the correct...

Question 15

Which of the following molecules is expected to have the highest melting point?

Accepted Answer

NaCl has a significantly higher melting point compared to the other molecules due to its strong ionic bonds. The other molecules are covalent compounds with weaker intermolecular forces and therefore have lower melting points.

Question 16

How many electrons are in the valence shell of I in IF₄^-?

Accepted Answer

Iodine (I) in IF4^- has 7 valence electrons, gains 1 from the negative charge, and shares 4 electrons with 4 fluorine atoms, totaling 12 electrons in the valence shell.

Question 17

In general,at room temperature

Accepted Answer

Ionic compounds generally have high melting and boiling points, making them solid at room temperature, while covalent compounds can have a range of melting and boiling points depending on their molecular structure, which can result in them being solid, liquid, or gas at room temperature. Therefore, option B is the most accurate statement.

Question 18

Identify the fourth-row element X that forms the ion.

Accepted Answer

The answer of Identify the fourth-row element X that forms...

Question 19

How many lone pairs of electrons are on the I atom in IF₅?

Accepted Answer

In the given molecule IF₅, the I atom has one lone pair of electrons.

Question 20

Based on the indicated electronegativities,arrange the following in order of increasing ionic character: CsBr,LaBr₃,PBr₃,MgBr₂.

Accepted Answer

The answer of Based on the indicated electronegativities,arrange the following...

Quiz 7: Covalent Bonding and Electron-Dot Structures

Arrange the following in order of increasing ionic character: Al₂S₃,MgS,Na₂S,P₄S₃,S₈.

When melting S₈, forces must be overcome and S₈ is expected to have a melting point than MgS.

How many of the σ bonds in H₂SO₄ are coordinate covalent bonds?

The nitrogen-nitrogen bond in :N N: has a bond order of

A::A represents

Which is the most acceptable electron dot structure for N₂H₂?

How many lone pairs are on the Br atom in BrI₂^-?

NO₂^- is be expected to have

Elements that can accommodate more than eight electrons in their valence shell occur only in periodic table row

Consider a molecule with the following connections: When a valid electron dot structure is written,how many double bonds will the molecule contain?

In the most acceptable electron-dot structure for carbonyl fluoride,COF₂ the central atom is

The electronegativities for the elements vary from 0.7 for cesium to 4.0 for fluorine.The electronegativity for iodine is 2.5.Based entirely on the general guidelines for electronegativities and bond character,

In the electron dot structure of HCN,the bond order of CN is

How many lone pairs in the correct electron dot structure of O₃?

Which of the following molecules is expected to have the highest melting point?

How many electrons are in the valence shell of I in IF₄^-?

In general,at room temperature

Identify the fourth-row element X that forms the ion.

How many lone pairs of electrons are on the I atom in IF₅?

Based on the indicated electronegativities,arrange the following in order of increasing ionic character: CsBr,LaBr₃,PBr₃,MgBr₂.

Quiz 7: Covalent Bonding and Electron-Dot Structures

Arrange the following in order of increasing ionic character: Al2S3,MgS,Na2S,P4S3,S8.

When melting S8,________ forces must be overcome and S8 is expected to have a ________ melting point than MgS.

How many of the σ bonds in H2SO4 are coordinate covalent bonds?

The nitrogen-nitrogen bond in :N N: has a bond order of

A::A represents

Which is the most acceptable electron dot structure for N2H2?

How many lone pairs are on the Br atom in BrI2-?

NO2- is be expected to have

Elements that can accommodate more than eight electrons in their valence shell occur only in periodic table row

Consider a molecule with the following connections: When a valid electron dot structure is written,how many double bonds will the molecule contain?

In the most acceptable electron-dot structure for carbonyl fluoride,COF2 the central atom is

The electronegativities for the elements vary from 0.7 for cesium to 4.0 for fluorine.The electronegativity for iodine is 2.5.Based entirely on the general guidelines for electronegativities and bond character,

In the electron dot structure of HCN,the bond order of CN is

How many lone pairs in the correct electron dot structure of O3?

Which of the following molecules is expected to have the highest melting point?

How many electrons are in the valence shell of I in IF4-?

In general,at room temperature

Identify the fourth-row element X that forms the ion.

How many lone pairs of electrons are on the I atom in IF5?

Based on the indicated electronegativities,arrange the following in order of increasing ionic character: CsBr,LaBr3,PBr3,MgBr2.

Arrange the following in order of increasing ionic character: Al₂S₃,MgS,Na₂S,P₄S₃,S₈.

When melting S₈, forces must be overcome and S₈ is expected to have a melting point than MgS.

How many of the σ bonds in H₂SO₄ are coordinate covalent bonds?

Which is the most acceptable electron dot structure for N₂H₂?

How many lone pairs are on the Br atom in BrI₂^-?

NO₂^- is be expected to have

In the most acceptable electron-dot structure for carbonyl fluoride,COF₂ the central atom is

How many lone pairs in the correct electron dot structure of O₃?

How many electrons are in the valence shell of I in IF₄^-?

How many lone pairs of electrons are on the I atom in IF₅?

Based on the indicated electronegativities,arrange the following in order of increasing ionic character: CsBr,LaBr₃,PBr₃,MgBr₂.