Which will have largest `DeltaT_(b)`?

1 mol each of the following compounds is dissolved in 1 L of solution. Which will have the largest Delta T_(b) value ?

Which of them will have largest atomic radii:

Which of the following will have largest size?

Which among the following will have largest size ?

In the hierarchy of classification, which grouping will have the smallest number of organisms with a maximum of characteristics in common and which will have the largest number of organisms ?