Answer:
9000 BC
Explanation:
Although various copper tools and decorative items dating back as early as 9000 BCE have been discovered, archaeological evidence suggests that it was the early Mesopotamians who, around 5000 to 6000 years ago, were the first to fully harness the ability to extract and work with copper.
In electromagnetic waves, energy is transferred through vibrations of electric and magnetic fields. In sound waves, energy is transferred through vibration of air particles or particles of a solid through which the sound travels.
Answer:
1..... nucleus
2......electron cloud
3.......protons
4........Neutrons
5..........electron
6............electrons
7...............Isotopes
8.....,...........ions
9....................charge
Answer: 0.002 M
Explanation:
The balanced chemical equation for ionization of 
in water is:
According to stoichiometry :
1 mole of ionizes to give =2 mole of 
ions
0.001 mole of ionizes to give = 
mole of ions
Thus of a solution of 0.001 M aqueous sulfuric acid is 0.002 M
