For the reaction, Ra + 2 HF --> RaF2 + H2, calculate the percent yield of radium fluoride if 300 grams of radium react with excess hydrofluoric acid (HF) to yield 295 g of radium fluoride.

List four observations that indicate that a chemical reaction may be taking place

Which element is the least metallic between cadmium, silver, zinc, or iron?

The solid xy decomposes into gaseous x and y: xy(s) m x(g) + y(g) kp = 4.1 (at 0 °c) if the reaction is carried out in a 22.4 l container, which initial amounts of x and y will result in the formation of solid xy?