A piece of pure metal, like copper or iron, comprises metal atoms, which are surrounded by electrons of moving force which drift free from each other's metal. The attraction between free - floating valence electrons and positive metal ions results in metallic bonds.
The lack of a number preceding the carbon symbol C and the compound formula CO2 shows that there is one carbon atom and one carbon dioxide molecule. Subscript numbers in chemical formulas represent the number of atoms or molecules immediately preceding the subscript.
1
the lower the number the higher the ph and the more acidic it is