The following are scientific observations which led to development and changes of periodic table: Dmitri Mendeleev is the first periodic table organized 63 known element according to its properties, organized into rows and columns and inscribed name, mass and chemical properties on each element. Julius Lothar Meyer who independently worked in Germany with Ernest Rutherford. They experimented with 38 metals and found out that the positive charge of each element nucleus increased by one from element to element and organized the periodic table that tip to modern explanation of atomic number and the recognition of atomic number was the basis for organization of periodic table.
Answer:
negative
Explanation:
Entropy is a measure of the "disorder" in a system.
In this reaction, the amount of disorder decreases. This is because one gas molecule (NH₃) has more order than two gas molecules (N₂ and H₂). Therefore, the entropy change should be negative.
The particles of gases have more kinetic energy than liquids and gases.
Explanation:
- We know that in case of solids the molecules are very tightly packed , in case of liquids the molecules are loosely packed and lastly in case of gases the molecules are very loosely packed.
- As we known in case of solids energy present is very less and in case of liquids energy present is more than solids and lastly in case of gases the energy present is most.
- Gases have more kinetic energy because the particles present in gaseous form can move easily without any obstruction.
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