Kg are units of mass, and ml are units of volume. If you are trying to find out how many grams of a solid are dissolved in 500 ml of a solution, then you need the molarity of the solution.
One half a kilo. The prefix "kilo" (symbol k) in the International System of Units (SI) and other systems, which denotes 103, it means one thousand. Therefore, there are 1,000 grams (g) in a kilogram...