Calculate the mass of water in which 1.00 g of MgSO4.7H20 should be dissolved so that the resulting solution will be 20.0% MgSO4 and 80.0% water by mass. (MgSO4•7H20 consists of 51.17% H20 and 48.83% MgSO4 by mass)

The phase where ice changes directly to gas is called sublimation 

  the volume of  0.220 m k2s    solution  required  to  completely  react with 175 ml  of 0.115m co(no3)2  calculate the moles  of co(no3)2 =  molarity x volume/1000175 x0.115/1000= 0.02  moleswrite  the reacting  equationk2s(aq)  +  co(no3)2  = 2 kno3(aq)  + cos(s)by  use  of mole ratio between k2s to co(no3)2 which  is  1: 1 the moles of k2s is therefore = 175  x0.115/1000= 0.02  molesvolume = moles/molarity=0.02/0.22=0.09  ml  of k2s