which of the following compounds have polar bonds and a net dipole moment?
a) H3COH
b) H3CCOCH3
ALSO PLEASE CHECK THIS, RANK THE FOLLOWING FROM MOST TO LEAST ACIDIC COMPOUND:
A)H2SO4>H3CCO2H>H20
B)H3CCH2NH2>H3CCH2OH>H3CCO2H
Both a and b have polar bonds and a net dipole moment.
H2SO4 is most acidic. H2O least.
CH3COOH is most acidic. CH3CH2NH2 is least.
Why is CH3CH2NH2 the least acidic?
The NH2 group in organic chemistry is an amine group and they are basic. Think of ammonia, NH3. This is just like ammonia except CH3CH2 roup has been substituted for one of the H on the NH3. The N has a lone pair of electrons which can accept a proton and that makes it a base.
To determine if a compound has polar bonds and a net dipole moment, we need to consider the molecular geometry and the nature of the bonds within the molecule.
For a bond to be polar, there must be a difference in electronegativity between the atoms involved. In general, if the difference in electronegativity between two atoms is greater than 0.5, the bond is considered polar. Additionally, the overall molecular geometry of the compound must not be symmetrical, leading to a net dipole moment.
Now, let's analyze each of the compounds:
a) H3COH:
In this compound, there is an oxygen atom bonded to a hydrogen atom. The electronegativity of oxygen is greater than that of hydrogen, indicating a polar bond between them. However, the overall molecular geometry is symmetrical. The dipole moments of the polar bonds cancel each other out, resulting in no net dipole moment. Therefore, this compound does not have a net dipole moment.
b) H3CCOCH3:
Here, there are two carbon atoms bonded to each other, and there are hydrogen atoms bonded to the carbon atoms. The electronegativity difference between carbon and hydrogen is small, so the carbon-hydrogen bonds are considered nonpolar. However, there is an oxygen atom bonded to one of the carbon atoms. The carbon-oxygen bond is polar due to the electronegativity difference between carbon and oxygen. Additionally, the overall molecular geometry is asymmetrical, resulting in a net dipole moment. Therefore, this compound has both polar bonds and a net dipole moment.
Ranking the following compounds from most to least acidic:
A) H2SO4 > H3CCO2H > H2O:
To determine the acidity of a compound, we need to consider the stability of the conjugate base formed when the compound donates a proton (H+). In this case, the stability of the conjugate base increases as we move from left to right in the list.
H2SO4 (sulfuric acid) is the most acidic compound because it forms a stable conjugate base (HSO4-). It is a strong acid and donates both of its protons readily.
H3CCO2H (acetic acid) is less acidic than H2SO4 but still more acidic than H2O. It forms the acetate ion (CH3CO2-) as its conjugate base.
H2O (water) is the least acidic compound in this list. It donates a proton less readily and its conjugate base (OH-) is less stable compared to the other two compounds.
B) H3CCH2NH2 > H3CCH2OH > H3CCO2H:
Following the same reasoning as before, we can rank the compounds based on the stability of their conjugate bases.
H3CCH2NH2 (ethylamine or CH3CH2NH2) is the most acidic compound in this list because it forms the ethylammonium ion (CH3CH2NH3+) as its conjugate base. The amino group (NH2) is a stronger base than the hydroxyl group (OH) and the carboxylate group (CO2-) in the other compounds.
H3CCH2OH (ethanol) is less acidic than H3CCH2NH2 but more acidic than H3CCO2H. It forms the ethoxide ion (CH3CH2O-) as its conjugate base.
H3CCO2H (acetic acid) is the least acidic compound in this list. It forms the acetate ion (CH3CO2-) as its conjugate base.
Remember that these rankings are based on relative acidity and do not reflect the actual numerical values of the acidity constants. The actual acidity constants may vary depending on the specific conditions.