Answer:
d. p3-
Explanation:
Phosphorus has fifteen electrons in its orbitals and five electrons in its outermost shell. An atom is said to have noble gas configuration when it has eight electron in its outermost shell.
In order to have eight electrons in its outermost shell, phosphorus must accept three electrons and form an ion of the sort P^3-. This ion now has eighteen electrons (argon configuration) and eight electrons in the outermost shell.
Answer:
B
Explanation:
The Niels Bohr's atomic model superior to all the earlier models is because it showed how the electron could orbit the nucleus without falling into it
Electron requires energy to move from ground state to excited state(higher energy levels). Hence option 1 is correct. Hope this helps!
The temperature for the reaction is calculated as follows
delta H/ delta S
delta H=-70 Kj
delta S =-0.300 kj/k
temperature is therefore = -70kj/-0.300kj/k =233.33 K
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.