Answer:
B
Explanation:
it is the energy stored in the chemical bonds of a substance
The liquids hexane
and water are placed in a test tube. The test tube is stoppered, shaken, and
placed in a test tube rack. The liquids separate into two distinct
layers because hexane and water have different molecular polarities. The answer
is number 2.
Answer: The given statement is false.
Explanation:
Precipitation reaction is defined as the chemical reaction in which two aqueous solution upon mixing together results in the formation of an insoluble solid.
For example, 
Here AgCl is present in solid state so, it is the precipitate.
But it is not necessarily true that two aqueous solutions will always result in the formation of a precipitate.
For example, 
Hence, we can conclude that the statement precipitation reactions always occur when two aqueous solutions are mixed, is false.
I believe the answer is A.