Are these correct?
Rank the following species in order of increasing acidity. Explain your reasons of ordering them as you do.
NH3 ,H2SO4, CH3OH, CH3COOH
CH3COOH > H2SO4> CH3OH >NH3
Rank the following species in order of increasing basicity. Explain your reasons of ordering them as you do.
CH3O- CH3COOH CH3COO- NaOH NH2- HSO4-
CH3O- > CH3COO- > NH2- > HSO4- > CH3COOH > NaOH
NH3 ,H2SO4, CH3OH, CH3COOH
I don't know HOW you arrived at your answer but we all know CH3COOH is a weak acid, H2SO4 is a strong acid, NH3 is a weak base and CH3OH for all practical purposes is neutral. So from most basic to most acidic, (;i.e., least acidic to most acidic) we have
NH3 < CH3OH < CH3COOH < H2SO4
You may want to review your text and notes on this or perhaps the meaning of < and >.
To rank the species in order of increasing acidity, you need to consider their properties as acids and bases. Acidity refers to the ability of a species to donate a proton (H+ ion) in a chemical reaction. The more easily a species donates a proton, the stronger the acid.
To determine acidity, you can look at these key factors:
1. Stability of the conjugate base: A stronger acid will have a more stable conjugate base. When an acid donates a proton, it forms a conjugate base. The stability of this base affects the acid strength.
2. Electronegativity and atom size: Acidity tends to increase as electronegativity increases or when the atomic size increases. More electronegative atoms or larger atoms tend to stabilize the negative charge on the conjugate base, making the acid stronger.
3. The availability of electrons: Density of electron cloud affects the ability to donate or accept protons. Higher electron density makes the species more basic, while lower electron density makes it more acidic.
Based on these factors, let's analyze the given species in order to rank them:
1. NH3 (Ammonia): Ammonia is a weak base because it can accept a proton but does not readily donate one. It has a lone pair of electrons, which can accept a proton, but it does not have a strong tendency to donate a proton. Therefore, it is the least acidic species in the list.
2. H2SO4 (Sulfuric acid): Sulfuric acid is a strong acid as it readily donates a proton. It has two acidic hydrogen atoms and can form a stable and highly electronegative conjugate base (HSO4-). Hence, it is the most acidic species in the list.
3. CH3OH (Methanol): Methanol is a neutral species and not considered an acid or a base under normal conditions. It does not readily donate or accept protons. Therefore, it is less acidic than sulfuric acid but more acidic than NH3.
4. CH3COOH (Acetic acid): Acetic acid is a weak acid that can donate a proton to a base. It has a relatively stable conjugate base (CH3COO-) and a moderate tendency to donate protons. Therefore, it is less acidic than sulfuric acid but more acidic than methanol.
Based on this analysis, the correct ranking from least acidic to most acidic is:
NH3 < CH3OH < CH3COOH < H2SO4
For ranking the species in increasing basicity, you can apply similar principles with a focus on the ability to accept a proton (H+ ion) instead of donating it.
CH3O- (Methoxide ion): Methoxide is a strong base as it can easily accept a proton. It has a lone pair of electrons that readily accepts a proton.
CH3COO- (Acetate ion): Acetate ion is a weaker base compared to methoxide ion. While it can accept a proton, its ability to do so is weaker due to the presence of electron-donating alkyl groups (CH3). This reduces its basicity.
NH2- (Amide ion): The amide ion is even weaker as a base. It can accept a proton, but the nitrogen atom is less electronegative than the oxygen atom in acetate ion. This decreases its ability to stabilize a negative charge, making it less basic.
HSO4- (Hydrogen sulfate ion): The hydrogen sulfate ion can accept a proton, but its basicity is reduced compared to the previously mentioned species due to the presence of negative charges and electronegative oxygen atoms.
CH3COOH (Acetic acid): Acetic acid is considered a weak base due to its moderate tendency to accept a proton. It can act as an acid by donating a proton, but it can also receive a proton and act as a base.
NaOH (Sodium hydroxide): Sodium hydroxide is a strong base that readily donates a proton. It can easily provide hydroxide ions (OH-) in reactions.
Based on these considerations, the correct ranking from least basic to most basic is:
CH3O- < CH3COO- < NH2- < HSO4- < CH3COOH < NaOH
I apologize for any confusion caused. Let me provide a step-by-step explanation for the order of acidity and basicity for the given species.
Ranking of acidity:
1. NH3: Ammonia (NH3) is a weak base and does not have any acidic properties.
2. CH3OH: Methanol (CH3OH) is a neutral compound and does not have any acidic properties.
3. CH3COOH: Acetic acid (CH3COOH) is a weak acid. It can donate a proton (H+) in solution, making it more acidic than NH3 and CH3OH.
4. H2SO4: Sulfuric acid (H2SO4) is a strong acid. It can easily donate two protons (H+) in solution, making it the most acidic compound among the given species.
Therefore, the correct rank of increasing acidity is NH3 < CH3OH < CH3COOH < H2SO4.
Ranking of basicity:
1. CH3O-: Methoxide ion (CH3O-) is a strong base due to the presence of a negative charge on oxygen.
2. CH3COO-: Acetate ion (CH3COO-) is a weak base but relatively stronger than NH2- and HSO4-. It can accept a proton (H+) in solution.
3. NH2-: Amide ion (NH2-) is a weak base. It can accept a proton (H+) in solution but to a lesser extent than CH3COO-.
4. HSO4-: Bisulfate ion (HSO4-) is a weak base and can accept a proton (H+) in solution but to a lesser extent than NH2- and CH3COO-.
5. CH3COOH: Acetic acid (CH3COOH) is a weak acid, and therefore, not considered in ranking basicity.
6. NaOH: Sodium hydroxide (NaOH) is a strong base and was not included in the original list. However, it should be noted that NaOH is a stronger base than all the mentioned species.
Therefore, the correct rank of increasing basicity is CH3O- < CH3COO- < NH2- < HSO4- < CH3COOH (not considered) < NaOH.