<span>A. The Russian chemist Dmitri Mendeleev </span>
Answer:
the valency of oxygen is -2
Answer: Bismuth (Bi) , Nitrogen family
Explanation:
As the element has 5 valence electrons in the sixth energy level, which mens it belongs to 6th period as the valence electron has entered the 6th energy level.
Now as the electrons are filled according to afbau's rule , the electronic configuration of the element will be :
![[Xe]4f^{14}5d^{10}6s^26p^3](https://tex.z-dn.net/?f=%5BXe%5D4f%5E%7B14%7D5d%5E%7B10%7D6s%5E26p%5E3)
Now as the atomic number of element is equal to the number of electrons in a neutral atom , the atomic number is 83 and the element is Bismuth (Bi). As the last electron enters p -subshell , it is a p block element. It lies in group 15 which is nitrogen family.
<span>According to this information, chloroform definitely should be stored </span>in <span>in a closed, dark container in the fume hood</span>. As you can see in the text represented above, there is a sentence which poses as a prompt for you''it is sensitive to light'' .
I am pretty sure it will help you! Regards.
Answer:
Hard water is water that has high mineral content, Soft water is free from dissolved salts of such metals as calcium, iron, or magnesium
Explanation: