Answer:
A. weak acid and its conjugate base
Explanation:
A buffer solution can be made with a weak acid and conjugate base or a weak base and conjugate acid.
This may help you:
https://chem.libretexts.org/Bookshelves/Physical_and_Theoretical_Chemistry_Textbook_Maps/Supplemental_Modules_(Physical_and_Theoretical_Chemistry)/Acids_and_Bases/Buffers/Introduction_to_Buffers
2Ca3(PO4)2 + 6SiO2 + 10C ---> P4 + 6CaSiO3 + 10CO
1 mole of Ca3(PO4)2 = 310g
1 mole of P4 = 124g
according to the reaction:
2*310g Ca3(PO4)2----------------124g P4
x g Ca3(PO4)2 ------------------------ 30g P4
x = 150g Ca3(PO4)2
so, your answer is good
The columns of the periodic table, also referred to as "groups" contain elements with similar reactive properties, due to these elements having a similar configuration of electrons in their outer shell.
"Endothermic" is the way among the following choices given that you would <span>classify the following chemical reaction, in terms of energy. The correct option among all the options that are given in the question is the second option or option "B". I hope that the answer has come to your help.</span>
The one with higher mass has a higher density because it fits more mass into the same amount of space (volume).