List in increasing order of expected Rf values in a TLC experiment: salicylic acid, toluene, and benzophenone.

To determine the expected Rf values for the TLC experiment, we need to consider the polarity of the compounds. The Rf value is influenced by the polarity of the compound and the polarity of the mobile phase (solvent). Compounds that are more polar tend to have smaller Rf values.

In this case, we have salicylic acid, toluene, and benzophenone. Let's examine the polarity of each compound:

1. Salicylic acid: Salicylic acid has a relatively high polarity due to the presence of the carboxylic acid group (-COOH). This compound is expected to have the highest Rf value among the three.

2. Benzophenone: Benzophenone is moderately polar. It contains a carbonyl group (-C=O), which imparts some polarity to the molecule. It is expected to have a lower Rf value compared to salicylic acid but higher than toluene.

3. Toluene: Toluene is non-polar since it consists only of carbon and hydrogen atoms. It lacks any polar functional groups. Thus, it is expected to have the lowest Rf value among the compounds mentioned.

Based on the above information, the compounds can be listed in increasing order of expected Rf values in the TLC experiment as follows:

Toluene < Benzophenone < Salicylic acid

To determine the order of expected Rf (retention factor) values in a TLC (thin layer chromatography) experiment, you need to consider the polarity of the compounds involved. The Rf value is defined as the ratio of the distance traveled by the compound spot to the distance traveled by the solvent front on the TLC plate.

In general, a compound with a higher affinity for the stationary phase (adsorbent) will have a lower Rf value, as it will interact more strongly with the adsorbent and travel a shorter distance. Conversely, a compound with a higher affinity for the mobile phase (solvent) will have a higher Rf value, as it will travel a longer distance.

Now, let's analyze the expected Rf values for salicylic acid, toluene, and benzophenone based on their polarity:

1. Toluene: Toluene is nonpolar and has low affinity for the polar stationary phase in TLC. Therefore, it will have a relatively high Rf value.

2. Benzophenone: Benzophenone is moderately polar due to the presence of carbonyl groups (C=O). It will have a moderate Rf value compared to toluene and salicylic acid.

3. Salicylic acid: Salicylic acid is polar due to the presence of a carboxylic acid group (-COOH). It will have the lowest Rf value among the three compounds, as it has a higher affinity for the polar stationary phase.

Therefore, in increasing order of expected Rf values, the list would be: salicylic acid < benzophenone < toluene.