10-Which of the following(s) is/are correct? I- Doubling the column's length increases resolution by a factor of 1.41. II- In GC, solute molecules do not interact with mobile phase III- The purpose of split ratio in split injection mode is to control the amount of sample injected onto the column. A) I,II and III B) Only II C) Iand II D) Iand III E) II and III

The correct answer is D) I and III.<br /><br />I- Doubling the column's length increases resolution by a factor of 1.41. This statement is correct. The resolution of a column in chromatography is directly proportional to the square root of the column length. Therefore, if the column length is doubled, the resolution will increase by a factor of 1.41.<br /><br />II- In GC, solute molecules do not interact with mobile phase. This statement is incorrect. In gas chromatography (GC), the solute molecules interact with the mobile phase (gas) as they are carried through the column.<br /><br />III- The purpose of split ratio in split injection mode is to control the amount of sample injected onto the column. This statement is correct. In split injection mode, the sample is divided between the column and the split vent. The split ratio determines the percentage of the sample that goes to the column and the percentage that goes to the split vent.