explain the difference in boiling points of acetone and 1 proponol. (proponol higher) also explain the difference in water solubility of chloroethane and acetone. (acetone is soluble but not chloroethane)
Propanol boils higher because of hydrogen bonding. Acetone is more solute because it is more polar (like water and like dissolves like).
The difference in boiling points between acetone and 1-propanol and the difference in water solubility between chloroethane and acetone can be explained based on their molecular structures and intermolecular forces.
1. Difference in boiling points between acetone and 1-propanol:
The boiling point of a substance is the temperature at which its vapor pressure equals the atmospheric pressure. Generally, molecules with stronger intermolecular forces tend to have higher boiling points.
Acetone (CH3COCH3) has a lower boiling point compared to 1-propanol (CH3CH2CH2OH) because acetone has weaker intermolecular forces. Acetone molecules are held together by dipole-dipole interactions and London dispersion forces. These forces are relatively weak compared to the hydrogen bonding present in 1-propanol. Hydrogen bonding occurs when a hydrogen atom is covalently bonded to a highly electronegative atom (such as oxygen or nitrogen) and interacts with another electronegative atom in a neighboring molecule, resulting in stronger intermolecular forces.
1-Propanol can form hydrogen bonds between its hydroxyl (-OH) functional group and other 1-propanol molecules. These hydrogen bonds are stronger than the intermolecular forces present in acetone, leading to higher boiling points for 1-propanol. The additional hydrogen bonding allows 1-propanol molecules to be more tightly packed and requires more energy to break these stronger bonds, resulting in a higher boiling point compared to acetone.
2. Difference in water solubility between chloroethane and acetone:
Water solubility is determined by the intermolecular forces between the solute (the substance being dissolved) and the solvent (the substance doing the dissolving).
Acetone is highly soluble in water because it can form strong hydrogen bonds with water molecules through its own oxygen atom. These hydrogen bonds form stable interactions between acetone and water, allowing them to mix evenly and dissolve.
On the other hand, chloroethane (C2H5Cl) is not very soluble in water. Although chloroethane also contains a polar carbon-chlorine (C-Cl) bond, it cannot form extensive hydrogen bonds with water because it lacks a hydrogen atom bonded to an electronegative atom. Instead, chloroethane molecules are primarily bound by weaker London dispersion forces. These dispersion forces are not as strong as hydrogen bonding, making chloroethane less soluble in water compared to acetone.
In summary, the differences in boiling points and water solubility between acetone and 1-propanol are due to the variations in their intermolecular forces. Acetone has weaker forces compared to 1-propanol, resulting in a lower boiling point and higher water solubility. Similarly, acetone is more soluble in water than chloroethane due to the presence of stronger hydrogen bonding interactions.