What substance is 52.4 % potassium and 47.6 % chlorine?

15) a substance used in manufacturing gasoline consists of finely divided platinum supported on an inert solid. suppose that the platinum is formed by the high temperature reaction between platinum (iv) oxide and hydrogen gas. the other product is water. a) write and balance the equation b) how many grams of hydrogen are needed to produce 1.0 g of platinum metal? c) how many moles of water are produced at the same time? how many grams? ( show work, .)

Can someone me with these problems? see the attachment, .

How can a scientist assess whether a pure niobium (nb) sample is responsible for contaminating the lab with radioactivity? test the niobium sample to see whether it now contains other elements. test the niobium sample for the presence of niobium oxide compounds. heat the niobium, and see if the level of radioactivity in the lab increases. place the niobium under pressure, and see if the level of radioactivity in the lab increases.