Why would hydrogen bonding not occur between benzophenone and water? or would it and why?
Why does benzophenone and methyl alcohol H bond? And benzophenone and hexane don't? Why is there potential for H bonding between malonic acid and water and malonic acid and methyl alcohol? and no H bond between hexane and malonic acid?
I know H bonds occur when H is bonded to N, O, or F but I don't know the circumstances of each of the above cases?
Malonic acid has the -COOH group which is the O you are looking for. Water has the HOH and methyl alcohol has the CH3CH2OH. So all have that magic O atom to provide the negative charge. Hexane is a straight chain hydrocarbon. The H atoms on CH3CH2CH2CH2CH2CH3 are covalently bound and not charged; therefore, there is nothing to form a H bond with when in methyl alcohol. Of course the methyl alcohol can form H bonds with itself but that is the only possibility when mixed with hexane.
To determine whether hydrogen bonding can occur between different molecules, we need to consider the presence of hydrogen bond donors (HBDs) and hydrogen bond acceptors (HBAs) in each molecule. HBDs are typically hydrogen atoms bonded to electronegative elements (N, O, or F), while HBAs are the electronegative atoms themselves.
Let's break down the cases you mentioned:
1. Benzophenone and Water:
Benzophenone does not contain any hydrogen atoms bonded directly to N, O, or F, so it cannot act as an HBD. However, it does have an oxygen atom, which can serve as an HBA. Water, on the other hand, has both an oxygen atom (HBA) and hydrogen atoms bonded to it (potential HBDs). Therefore, hydrogen bonding can occur between water molecules but not between water and benzophenone.
2. Benzophenone and Methyl Alcohol:
Benzophenone contains an oxygen atom (HBA) and hydrogen atoms bonded to carbon (HBDs). Methyl alcohol (methanol) has both an oxygen atom (HBA) and hydrogen atoms bonded to it (HBDs). This allows the formation of hydrogen bonds between benzophenone and methyl alcohol.
3. Benzophenone and Hexane:
Both benzophenone and hexane do not have any hydrogen atoms directly bonded to N, O, or F, thus they lack the necessary components to form hydrogen bonds. Therefore, there is no potential for hydrogen bonding between benzophenone and hexane.
4. Malonic Acid and Water/Methyl Alcohol:
Malonic acid contains hydrogen atoms directly bonded to an oxygen atom (HBDs) and oxygen atoms (HBAs). Both water and methyl alcohol have the necessary components for hydrogen bonding: oxygen atoms (HBAs) and hydrogen atoms bonded to them (HBDs). Hence, hydrogen bonding can occur between malonic acid and both water and methyl alcohol.
5. Hexane and Malonic Acid:
Neither hexane nor malonic acid contains hydrogen atoms directly bonded to N, O, or F, so they lack the necessary components for hydrogen bonding. Consequently, there is no potential for hydrogen bonding between hexane and malonic acid.
Understanding the nature of hydrogen bond donors (HBDs) and hydrogen bond acceptors (HBAs) in molecules helps us determine whether or not hydrogen bonding is likely to occur between them.
Hydrogen bonding occurs when a hydrogen atom is bonded to a highly electronegative atom (such as nitrogen, oxygen, or fluorine) and interacts with the lone pair of electrons on another electronegative atom.
In the case of benzophenone and water, hydrogen bonding would not occur. Benzophenone does not contain any hydrogen atoms bonded to electronegative atoms. Therefore, it cannot form hydrogen bonds with water, which contains hydrogen atoms bonded to oxygen.
However, benzophenone can form hydrogen bonds with methyl alcohol. Methyl alcohol (methanol) contains a hydrogen atom bonded to an oxygen atom, which can form a hydrogen bond with the carbonyl group of benzophenone.
On the other hand, benzophenone and hexane do not form hydrogen bonds. Hexane is a nonpolar molecule that does not contain any electronegative atoms capable of forming hydrogen bonds. Thus, the hydrogen bonding potential is absent between benzophenone and hexane.
Regarding malonic acid, it can form hydrogen bonds with both water and methyl alcohol. Malonic acid contains two carboxylic acid groups, each of which has a hydrogen atom bonded to an oxygen atom. These hydrogen atoms can participate in hydrogen bonding with the lone pairs of electrons on water or methyl alcohol molecules.
However, there is no hydrogen bonding between malonic acid and hexane because hexane is nonpolar and lacks electronegative atoms capable of forming hydrogen bonds.