Which dye has the smallest molecular weight?

Which dye has the smallest molecular weight?

• A. Bromophenol Blue
• B. Xylene Cyanole
• C. None of the above
• D. Orange G

Answer: (D)

The main idea here is understanding how the sizes of tracking dyes relate to how far they travel in a gel during electrophoresis. The dye with the smallest molecular weight will migrate fastest and appear as the leading dye front. Among the dyes listed, Orange G has the smallest molecular weight. Bromophenol Blue is relatively large, and Xylene Cyanol FF is intermediate in size, both heavier than Orange G. Because Orange G is lighter, it moves through the gel more quickly under the same conditions, making it the fastest-propagating dye. This is why Orange G is the correct answer.

The main idea here is understanding how the sizes of tracking dyes relate to how far they travel in a gel during electrophoresis. The dye with the smallest molecular weight will migrate fastest and appear as the leading dye front.

Among the dyes listed, Orange G has the smallest molecular weight. Bromophenol Blue is relatively large, and Xylene Cyanol FF is intermediate in size, both heavier than Orange G. Because Orange G is lighter, it moves through the gel more quickly under the same conditions, making it the fastest-propagating dye. This is why Orange G is the correct answer.