Bioaccumulation refers to the accumulation of chemicals in a living organism. The compound or chemical accumulates at a rate faster than it is being metabolized or excreted by the organism. Chemicals bioaccumulate by binding to the proteins and fats in an organism while others bioaccumulate through the repeated consumption of contaminated organisms.
Pesticides containing chemicals that dissolve easily in fat but not in water tend to bioaccumulate. Pesticides that contain chemicals that can easily be metabolized by organisms do not bioaccumulate. In summary, the nature of the chemical used in pesticides and the capability of organisms to metabolize the said chemicals can dictate whether it will bioaccumulate or not.
2NaOH=Na2O +H2O
The coefficient of NaOH is 2
If you are wanting the equation to be balanced it would be: P4 + 6Cl2 → 4PCl3
The idea behind balancing chemical equations is that the number of atoms an element has on the reactants' side must be equal to the number of atoms it has on the products' side.
These atoms will become a part of different compounds once the reaction is completed, but they must always be in equal numbers on both sides.
So, look at iron first. One atom reacts, but two are produced - notice the 2 subscript iron has in Fe2O3. This means you must double the number of atoms on the reactants' side to reach an equality.
2Fe(s)+O2(g)→Fe2O3(s)
Now look at oxygen. Two atoms react, but three are produced. The trick here is to find a common multiple that will make the number of atoms equal on both sides.
The easiest way to do this is to multiply the atoms that react by 3, which will give you 6 oxygen atoms that react, and the atoms that are produced by 2 - this will get you 6 oxygen atoms produced.
2Fe(s)+3O2(g)→2Fe2O3(s)
However, notice that the iron atoms are unbalanced again. You have 2 that react, but 4 that are produced → multiply the atoms that react by 2 again, which will give you
4Fe(s)+3O2(g)→2Fe2O3(s)
Answer: 
Explanation:
Given
Initial mass 
half-life is 
At any time the left amount is given by
