Zn (s) -> Zn+2 (aq) + 2e-
Zn (s) with a neutral charge is oxidized and looses two electrons in the process to form ZnCl2 (aq) where Zn has a charge of 2+.
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.
Hydroponics is more than just another way to grow plants–the technology has the potential to change how we engage with food cultivation as a whole! For the first time since humans started tilling the land, modern hydroponics technology frees us from the soil beneath our feet, allowing us to bring food production indoors where we can layer in additional climate and lighting controls. The result is an ability to grow food anytime, anywhere in the world.
The answer is the third one because density is mass divided by volume so 80 divided by 10 is 8