Ernest develops a about the structure of the atom, starting from the idea that all atoms are made from different numbers of two particles, a heavy positively-charged one and a light negatively-charged one. By using this idea Ernest is able to explain the results of many different experiments on atoms.

What semimetal can form four single covalent bonds.

12. complete each of the following word equations for synthesis reactions. a. sodium + oxygen -> b. magnesium + fluorine -> 13. complete and balance the equations for the decomposition reactions. a. hgo -> [with the triangle heat symbol above the arrow] b. h2o(l) -> [with "electricity" written above the arrow]

Compare and contrast physical changes with chemical changes.