Period number on the periodic table used in a sentence

Gold (Au) is group 11 period 6 on the periodic table

Explanation:

i hope this helps... im not sure if i read the question correctly

2h2o2--> 2h2o + o2

this reaction is of the spontaneous decomposition of hydrogen peroxide down into water and oxygen.

add 2 molecules of hydrogen peroxide and 2 molecules of water. since oxygen is naturally diatomic, the total number of atoms of each element is now the same on both sides of the equation so it is balanced.

this may not be entirely correct but let me know.