Answer is: the atom is the smallest known particle of matter.
John Dalton claimed that atom is indestructible and a<span>ll atoms of a given element are identical in mass and properties.
</span>Thomson discovered electron and found the first evidence for isotopes<span> of a stable element.</span>
In order to balance this equation you need to count each element and how many of the individual elements are in the equation.
_H2+N2=2 NH3
You multiply the 2 (Which is the coefficient) by the 3 (which is the subscript) This would equal 6 which indicated there are 6 hydrogen atoms on the right side so the left side should also have 6 hydrogen atoms
The missing coefficient on the left side must multiple the 2 to become 6 hydrogen
Answer=3
Iodine- in most cleaning solutions