it takes 1 minute for a certain amount of potassium phosphate (KH2PO4) to dissolve in 100 grams of water at 50 °C.

Which of the following will most likely happen if the same sample of potassium phosphate is dissolved in 100 grams of water at 20 °C?

The sample will dissolve in exactly 1 minute.
The sample will dissolve in more than 1 minute.
The collision between particles of the sample will increase.
The collision between particles of the sample will remain constant.