Explanation:
Transfer of mass A into stagnant film B depends on the availability of driving force.
Whereas driving force is the pressure difference at the surface of A and the bulk.
As, 

Therefore, putting the given values into the above formula as follows.

= 
= 0.132 
Thus, we can conclude that the flux of A from a surface into a mixture of A and B is 0.132 
A water molecule consists of three atoms; an oxygen atom and two hydrogen atoms, which are bond together like little magnets.
An iron pot is made up of only one substance, iron. Iron is an element classified as a transition metal
Iron. Elementsare pure substances that are made up of one kind of atom. Pizza is not an element because it is a mixture of many substances. Water is a pure substance, but it contains two kindsof atom: oxygen and hydrogen.
Fluorine 20 (F - Atomic number 9 and atomic mass 20). Firstly we need to know what is beta decay. Beta decay occurs when one neutron changes into a proton and an electron therefore the atomic mass will remain the same as even though we loose a neutron it is replaced by a proton, the atomic number is always raised by 1 when one beta decay occurs. The produced electron is shot out of the nucleus at an incredible speed. This speedy electron we call a beta particle.
Ok now the reaction.
20 20 0
F -> Ne + e
9 10 -1
Remember the atomic number determines the nature of the element ( i.e what elemnt it is).
Hope this helps :).