We are given that 70.4% of the weight of the total 200 g of the concentration is made up of nitric acid, the remaining information is not required to solve the problem. Since water and nitric acid are the only components of the solution, the total weight of water is given by:
fe+s is a mixture of iron and sulphur and it can be separated by magnetic separation. But FeS is a compound formed by heating iron and sulphur together.it can't be separated by any method.