<u>Answer:</u> The amount of calcium hydroxide needed to react is 2.04 moles
<u>Explanation:</u>
We are given:
Moles of phosphoric acid = 1.36 moles
For the given chemical equation:
By Stoichiometry of the reaction:
2 moles of phosphoric acid reacts with 3 moles of calcium hydroxide
So, 1.36 moles of phosphoric acid will react with = 
of calcium hydroxide
Hence, the amount of calcium hydroxide needed to react is 2.04 moles
The answer is B. the occurrence of huge events in Earth's natural history
The geologic time scale is a system of chronological dating that relates geological strata to time. It is used by geologists, paleontologists, and other Earth scientists to describe the timing and relationships of events that have occurred during Earth's history.
I believe distillation is used to separate solvents of different kind as long as it is heated to its boiling temp
