Answer:
0.2615 g
Explanation:
Given that mass of the body = 120 lb
The conversion of lb to g is shown below as:-
1 lb = 454 g
So, 120 lb = 120*454 g = 54480 g
The substance is 
of the human body
So, Mass of that substance in the body of mass 54480 g is:-
<u>0.2615 g of that substance would be found in the body of a person weighing 120 lb.</u>
The molecular weight is the same as molecular mass. You find this by using the periodic table
The molar mass of Mg(NO3)2 is 148.3
It can be a compound or a single element. An element is a pure substance that cannot be separated into simpler substances by chemical or physical means. There are about 117 elements, but carbon, hydrogen, nitrogen and oxygen are only a few that make up the largest portion of Earth.
hopefully that helps
What do you mean by unlock all of them? Please explain
