Answer:
. A closed system allows only energy transfer but no transfer of mass. Example: a cup of coffee with a lid on it, or a simple water bottle. ... In reality, a perfectly isolated system does not exist, for instance hot water in a thermos flask cannot remain hot forever.
Explanation:
1) Atoms can not be subdivided. It has been changed as it is possible to divide an atom into Protons, Neutrons and Electrons as well as other smaller particles.
2) The regulations for the chemical mixture have always been altered to the rules for the chemical combination in the creation of organic compounds may be denied.
3)Atoms are of a particular element are identical in all respects i. e. they have same mass and similar properties.
It was modified. And according. to new search;
Atoms of the same element may not be always identical.
That would be the first option Ca(OH)2 + H2SO4 → CaSO4 + 2H2O.
The Ca replaces the H2 in H2SO4, and the H2 replaces the Ca is Ca(OH)2.
