Based on the given van der Waals constants, arrange these hypothetical gases in order of decreasing strength of intermolecular forces. Assume that the gases have similar molar masses. Rank from strongest to weakest intermolecular attraction. To rank items as equivalent, overlap them.

Gas a (L2?atm/mol2) b (L/mol)
Q 5.46 0.0305
D 4.16 0.0373
M 2.25 0.0428
R 1.34 0.0322

Astudent pours 10.0 g of salt into a container of water and observes the amount of time it takes for the salt to dissolve. she then repeats the process using the same amounts of salt and water but this time she slowly stirs the mixture while it is dissolving. the student performs the experiment one more time but this time she stirs the mixture rapidly. the dependent variable in this experiment is: time for salt to dissolve speed of stirring amount of water mass of salt