Bonding and Forces - AP Chemistry

H bonding is when a H is bonded to either N, O, or F. In the third molecule, the O is only double-bonded to the C; it is not bonded to a single H. All other choices have a N, O, or F bonded to a H

For hydrogen bonding to occur there must be a molecule with a hydrogen bonded to either F,O,N. This is present in water and methanol which both have O-H bonds. There can be hydrogen bonding between two water molecules, and there can be hydrogen bonding between two methanol molecules. The key to this problem is recognizing that it is asking for a situation in which hydrogen bonding is occuring between two separate molecules.

Hydrogen bonding is the association of a hydrogen and one of the three most electronegative elements F,O,N of neighboring molecules. The hydrogen, because it is bonded to one of these elements, aquires a partially positive charge, F,O, or N develops a partially negative charge. The partially positive hydrogen will associate, not bond, with the F,O, or N of a seperate molecule. Remeber that hydrogen bonding is an intermolecular property, so it is occuring between separate molecules.

Electronegative atoms disproportionately pull covalently bonded electrons toward themselves, which leaves hydrogen with partial positive character.

Differences in the physcal properties of substances is often due to differences in molecular structure. Intermolecular forces can have profound effects on physical properties such as boiling point. Substances with the same molecular formula can actually behave quite differently based on how the atoms in these substances are connected. Hydrogen bonding is a strong intermolecular force that often leads to higher boiling points in substances that can hydrogen bond when compared to substances of similar molecular weights that cannot hydrogen bond with one another. Thus the presence of hydrogen bonding in the unknown substance is the best answer.

When hydrogen is bonded to a highly electronegative atom (such as nitrogen, oxygen, and fluorine), the electrons are pulled more closely to the electronegative atom than to the hydrogen nucleus. This results in a partially positive charge on the hydrogen atom, which allows it to attract partially negative charged atoms on other molecules. This type of intermolecular force is called a hydrogen bond.

Carbon and hydrogen have very similar electronegativities, so the electrons are equally shared. This makes methane a nonpolar molecule. As a result, it is incapable of hydrogen bonding with other molecules.

Hydrogen bonding only occurs when hydrogen is bound to either oxygen, nitrogen, or fluorine. Only these atoms form a bond with hydrogen polar enough so hydrogen bonding to occur.

may participate in hydrogen bonding, which is one of the strongest intermolecular forces. Hydrogen bonding increases a substance's boiling point, and lowers its vapor pressure.

Butane has 13 sigma bonds. Ethane has 7 sigma bonds. Benzene has 12 sigma bonds. Lithium Hydroxide has 2 sigma bonds and water has 2 sigma bonds.

π bonds occur when there is greater than a single bond (double or triple bond). The only compound listed with double bonds or greater is CO2, meaning it is the one that contains the most π bonds.

Ag(NH3)3 has covalent bonds (N-H) and ionic bonds (Ag-N).

A hydrogen bond is an intermolecular force between a hydrogen atom and an electronegative atom (O, N, F) that are in close proximity. Hydrogen bonds can occur within a given molecule (intramolecular), but more commonly occur between adjacent molecules (intermolecular). A solution of Ag(NH3)3 would show hydrogen bonding between the hydrogen and nitrogen of nearby molecules. The compound would not show intramolecular hydrogen. Since the question asks only for intramolecular interactions (single molecule), hydrogen bonding cannot be an answer choice.

We know from Lewis structures that diatomic hydrogen will have a single bond, diatomic oxygen will have a double bond, and diatomic nitrogen will have a triple bond. Triple bonds are stronger than double or single bonds, and the stronger the bond, the shorter the bond length. Nitrogen will have the shortest bond length.

We also know that the longest bond will be weakest. This mean hydrogen, with its single bond, would have the longest bond length. The answer should be N2 < O2 < H2.

Triple bonds involve sharing a total of six electrons. They are shortest in length and store the most energy, making them difficult to break. These properties make triple bonds stronger than double or single bonds.

Coordinate covalent bonds form when one atom contributes two electrons to be shared between nuclei, as opposed to each atom sharing a single electron. Once formed, coordinate covalent bonds have essentially identical properties to any other single bonds.

Diatomic nitrogen, , contains a triple bond between the two nitrogen atoms. Since there are six electrons being shared, the bond is stronger and the atoms are being pulled closer together. Diatomic oxygen, , has a double bond, which is not as strong. Diatomic hydrogen, , has a single bond, which have a bond length greater than either a double or triple bond. Hydrochloric acid, , is an ionic compound and will have a bond length comparable to a single covalent bond.

Out of the five given functional groups, only alcohols do not contain a central atom which is double bonded (meaning those atoms have hybridization). The only central atom of an alcohol, the oxygen atom in , has single bonds to the R-group and a single hydrogen along with two lone pairs, giving it hybridization.

The alkyne, a hydrocarbon containing a triple bond, has one sigma bond, and two pi bonds, making a rod-like molecule with a bond angle of and hybridization. It is the only type of compound of the choices to have a triple bond, making it the only possibility.

The group indicated by the question consists of a carbon atom bonded to two oxygen atoms (one with a double bond, and one with a single bond). The carbon is also bonded to the rest of the hydrocarbon chain by a single sigma bond. Because this carbon atom only has three electron domains and has no lone pairs, trigonal planar is the molecular geometry that best describes this piece of the larger molecule. The atoms bonded to this carbon molecule sit at from each other, an even division of the single plane in which these atoms sit.

has two sigma bonds between oxygen and hydrogen. It also has two pair of lone electrons on oxygen. The number of bonds and lone pairs contribute to the hybridization. For example, if a molecule consists of one sigma bond and one electron pair, the hybridization would be sp. If the molecule consists of two sigma bonds and one electron pair, the hybridization would be , and so forth.

LiOH displays ion-dipole IMF, H2O displays hydrogen bonding, and CO2 displays dipole-dipole. Ion-dipole is greater than hydrogen bonding as an IMf, and hydrogen bonding is greater than dipole-dipole.

This is butanol. It is an alcohol; OH is the prime example of hydrogen bonding, which is the strongest intermolecular force.

Ionic bonds are the strongest type of bonds, followed by covalent bonds, hydrogen bonds, and lastly, van Der waals forces.