Answer:

Explanation:
Number of molecules of water = 
= Avogadro's number = 
Number of moles is given by


The number of moles of water is
.
Answer:Chewing in the mouth breaks food into smaller pieces
Explanation: all you are doing is breaking down the food in your mouth
Answer: 27 neutrons
Explanation:
Recall that the number of protons in the nucleus of an atom = Atomic number.
Hence, Calcium with mass number 47 and atomic number 20 will have 20 protons
Therefore, since Mass number = number of protons + neutrons
47 = 20 + neutrons
Neutrons = 47 - 20 = 27
Thus, there are 27 neutrons in radioactive calcium nucleus.
Answer:
in the air and soil
in drinking water
on and inside the human body
Explanation: Hope that helps