Answer:
because its stronger than the 40% alcohol
Explanation:
The reason its recommended by doctors to use is
70% isopropyl alcohol solution kills microorganisms by dissolving plasma membrane of the cell wall.
the plasma membrane of gram-negative bacteria consists of a thin layer of peptidoglycan that can easily get destroyed by the alcoholo. Ispropyl alcohol is most commonly used as a disinfectant in pharmaceutical industries. the important thing is that only 70% solution of isopropyl alcohol acts as a disinfectant killing all surface microorganisms. it is used to disinfect hands and equipment surface in pharmaceuticals
hope it helps
studywell
