What colour change would you see on adding litmus solution to a solution of phosphorus pentoxide

Which actions would increase the rate at salt dissolves in water? stir the water? crush the salt? use less water? heat the water? cool the salt

Which aqueous solution of ki freezes at the lowest temperature? 1) 1 mol of ki in 500. g of water 2) 2 mol of ki in 500. g of water 3) 1 mol of ki in 1000. g of water 4) 2 mol of ki in 1000. g of water

One student said that the investigation was not valid (a fair test). write a plan for the investigation that includes improvements to the method and apparatus