An adhesive dealer receives an order for 3000 lb of an adhesive solution containing 13% polymer by weight. On hand are 500 lb of 10% solution and very large quantities of 20% solution and pure solvent. Calculate the weight of each that must be blended together to fill this order. Use all of the 10% solution.

Explanation:

The mass of polymer in the order recieved is:

The mass of polymer in the 10% solution is:

So to solve this problem, we need to add (390-50) 340 lb of polymer that comes from the 20% solution.

We calculate the mass of the 20% solution that would contain 340 lb of polymer:

So far, in total we have a solution that weighs (1700+500) 2200 lb and contains 390 lb of polymer.

Thus, in order to reach the required mass of solution (and percentage of polymer by weight), we add (3000-2200) 800 lb of pure solvent.

the dissolution of polymer can be thermodynamically described in 2 steps.

answer is: nuclear fusion produces elements that are heavier than helium.

nuclei combine to form a heavier nucleus, releasing energy.  

for example, fusion of hydrogen atoms at the sun.  

this fusion nuclear reaction is in the inner core of the sun and hydrogen (atomic number 1) is conveted into helium (atomic number 2).  

the inner core is the central region of the sun and all solar energy is produced in the core by nuclear fusion.