Which scientist offered proof that atoms exist?
a. aristotle
b. democritus
c. john dalton
d. isaac newton

b. Democritus

Explanation:

The greek philospher Democritus around 400 B.C proposed first atomic theory. He proposed the fact that the world is made of two things such as void (empty space) and the tiny particles called as atoms. He said that the atoms are indestructible, small and invisible. These atoms cannot be broken as they are the smallest particles. The atoms combine to form molecules, ions, rocks and other entities.

each  column  of the  table  is called a group. elements in a group share similar properties. groups are  read  from  top  to  bottom. metal. metalloid. nonmetal. solid. liquid. gas. fe. hg. o.  2. 3. 4. 5. 6. 7. 8. 9.  2. beryllium. 9.012. 4.  sodium. 22.990.  11. 3.  magnesium. 24.305.  12.  potassium. 39.098.  19. 4.  calcium. 40.078.  20. i guess  i  

metals are good conductor of electricity. it has free electrons on their surface. according to electron pool theory, each atom present in a metal crystal losses all of its valence electron and as a result a pool of free is form. these pool of electrons are free to move and   conduct electricity easily   while making metal as good conductor.

the correct answer is a. the ability of electrons to flow throughout the metal.

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