Answer:
D H2PO4– + HPO42–
Explanation:
The acid dissociation constant for
are
respectively.



The reason while option D is the best answer is that, the value of pKa for both
lies on either side of the desired pH of the buffer. This implies that one is slightly over and the other is slightly under.
Using Henderson-Hasselbach equation:

<u>Answer</u>:
the continents of earth were clustered together in formation that a scientist named Pangaea.
<u>Explanation</u>:
Before 300 million years ago, our earth was not made up of 7 different continent what we have now. Instead it was single huge mass land that was surrounded by a single ocean called Panthalassa. A lot of migration and collision lead to the formation of Pangaea. An Scientist named Albert Wegener gave the name Pangaea. Later, Pangaea was broken into Gondwanaland and Laurasia.These Lands were then divided into 7 continents.
Answer:
The nucleus contains the majority of an atom's mass because protons and neutrons are much heavier than electrons, whereas electrons occupy almost all of an atom's volume. The diameter of an atom is on the order of 10−10 m, whereas the diameter of the nucleus is roughly 10−15 m—about 100,000 times smaller.
Explanation:
It starts to dim. I hope this helps you.
this equation is balanced.