Which of the following acids is expected to be the strongest acid?
CH2F-COOH
CF3-COOH
CH3-COOH
CCl3-COOH
CBr3-COOH
i chose ccl3-cooh
Induction will give you the correct answer. Which atom is the most electronegative?
Steve is right. CCl3COOH is not it.
To determine which of the given acids is expected to be the strongest acid, we need to consider their molecular structures and the factors that influence acid strength.
The strength of an acid is determined by its ability to donate a proton (H+) to a water molecule. Two factors that strongly influence acid strength are the electronegativity of the atom bonded to the acidic hydrogen and the stability of the resulting conjugate base.
In general, as the electronegativity of the atom bonded to the acidic hydrogen increases, the acidity of the molecule also increases. This is because more electronegative atoms can stabilize the negative charge of the conjugate base, making the molecule more likely to donate a proton.
In the given molecules, we have the following:
- CH2F-COOH: The acidic hydrogen is bonded to a carbon atom, which is less electronegative than any of the other options. This molecule is not expected to be the strongest acid.
- CF3-COOH: The acidic hydrogen is bonded to a carbon atom that is bonded to three highly electronegative fluorine atoms. The presence of these strongly electronegative atoms increases the acidity of the molecule. This makes CF3-COOH a stronger acid than CH2F-COOH, but it may not be the strongest acid among the options.
- CH3-COOH: The acidic hydrogen is bonded to a carbon atom, similar to CH2F-COOH. This molecule is not expected to be the strongest acid.
- CCl3-COOH: The acidic hydrogen is bonded to a carbon atom that is bonded to three highly electronegative chlorine atoms. The presence of these strongly electronegative atoms increases the acidity of the molecule. CCl3-COOH is expected to be a stronger acid than CF3-COOH.
- CBr3-COOH: The acidic hydrogen is bonded to a carbon atom that is bonded to three bromine atoms. Bromine is less electronegative than chlorine, so the CBr3-COOH molecule is expected to be less acidic than CCl3-COOH.
Therefore, based on electronegativity and conjugate base stability, CCl3-COOH is indeed expected to be the strongest acid among the given options, making your choice of CCl3-COOH correct.