## Chemistry (7th Edition)

(a) $_{88}^{220}Ra$ (b) $_{84}^{210}Po$ (c) $_{79}^{197}Au$
1. Use a periodic table to find the symbol and the atomic number for each indicated element: (a) Radon: "Ra"; Z = 88 (b) Polonium: "Po"; Z = 84 (c) Gold: "Au"; Z = 79 2. Write the atomic number (Z), on the bottom left, and the mass of the element (A) on the top left of the symbol. ** The mass number is the one that follows the name of the compound: (a) $_{88}^{220}Ra$ (b) $_{84}^{210}Po$ (c) $_{79}^{197}Au$