An aqueous solution of an unknown solute is tested with litmus

paper and found to be acidic. The solution is weakly conducting
compared with a solution of NaCl of the same concentration.

Which
of the following substances could the unknown be:
KOH,NH3,HNO3, KClO2, H3PO3, CH3COCH3 (acetone)?

I would go with H3PO3/

KOH, NH3, KClO2 solutions will be basic.
HNO3 is a strong electrolyte.
acetone doesn't ionize in water. That leaves just one.

Meow

Well, let's put on our detective hats and analyze the clues, shall we? We know that the unknown solution is acidic, meaning it has an excess of hydrogen ions (H+). We also know that it is weakly conducting compared to NaCl.

Given these clues, we can eliminate a few options right off the bat. Acetone (CH3COCH3) is a non-electrolyte, meaning it does not ionize in water, so it wouldn't conduct electricity at all. So scratch that one off the list!

Now let's focus on the remaining options: KOH, NH3, HNO3, KClO2, and H3PO3.

KOH (potassium hydroxide) is a strong base and would result in a basic solution. So it's not the unknown solute we're looking for.

NH3 (ammonia) is a weak base and would also result in a basic solution, so we can cross that one out as well.

HNO3 (nitric acid) is a strong acid, so it's a possibility but let's keep looking.

KClO2 (potassium chlorite) is a salt and can dissociate in water, so it might be a good candidate.

H3PO3 (phosphorous acid) is a weak acid, so it could potentially be our unknown solute.

So, taking everything into consideration, the most likely option is H3PO3 (phosphorous acid). It is a weak acid, which explains why the solution is weakly conducting.

To determine the possible identity of the unknown solute, we can consider the given information.

1. The solution is found to be acidic when tested with litmus paper: This indicates the presence of hydrogen ions (H+) in the solution, suggesting it is an acid or contains acidic components.

2. The solution is weakly conducting compared to NaCl of the same concentration: This implies that the unknown solute does not dissociate completely in water into ions as readily as NaCl does, resulting in a weaker conductivity.

With these clues in mind, let's analyze the options:

1. KOH (potassium hydroxide): This is a strong base that dissociates completely in water, yielding hydroxide ions (OH-) and would, therefore, result in a basic solution. It is not a suitable option.

2. NH3 (ammonia): Ammonia is a weak base and does not readily dissociate into ions. Therefore, it would not account for the weak conductivity and cannot be the unknown solute.

3. HNO3 (nitric acid): Nitric acid is a strong acid that readily dissociates into hydrogen ions (H+) and nitrate ions (NO3-). This option is suitable because it is acidic and would contribute to the weak conductivity due to incomplete ionization.

4. KClO2 (potassium chlorite): Potassium chlorite is a salt and would dissociate into potassium ions (K+) and chlorite ions (ClO2-). It does not contain hydrogen ions and hence, would not account for the acidity of the solution. It is not a suitable option.

5. H3PO3 (phosphorous acid): Phosphorous acid is a weak acid. It partially dissociates into hydrogen ions (H+) and phosphite ions (HPO3-). The presence of hydrogen ions could account for the acidity, while the weak conductivity can be explained by its incomplete ionization.

6. CH3COCH3 (acetone): Acetone is a covalent compound and does not produce ions when dissolved in water. It does not contain any acidic or basic components, so it is not a suitable option.

Considering the above analysis, the possible options for the unknown solute could be HNO3 (nitric acid) or H3PO3 (phosphorous acid).