Answer:
chemical energy, Energy stored in the bonds of chemical compounds. Chemical energy may be released during a chemical reaction, often in the form of heat; such reactions are called exothermic.
According to the second order formula:
1/[At] = K t + 1/[Ao]
and when we have the K constant =0.0265 & we have t = 180 min & we have the initial concentration of A = 4.25 so by substitution:
1/[At] = 0.0265 X 180min + 1/4.25
1/[At] = 5
∴[At] = 1/5 = 0.2 m
Atomic mass of N from periodic table is 14 amu so atomic mass of N₂ will be 2 * 14 = 28 amu
This means that every mole of N₂ has mass equal to 28 g
Answer : The lowest numbered energy level where a 'd' sublevel is found is 3.
Explanation : According to the theory of order of electron filling;
The 4s orbitals is observed to have a lower energy than the 3d, and so the 4s orbitals are filled first.
It is known that 4s electrons are lost first during ionisation activity. Therefore, the electrons lost first will come from the highest energy level, furthest from the influence of the nucleus.
So, the lowest energy level where 'd' sub shell will be found is 3d.
Answer:
You can see that it is an endothermic reaction or heat is being absorbed for the change from magnesium to magnesium oxide. So it is an endothermic reaction. So these are the four reasons why we can say that burning of magnesium ribbon in the air is considered a chemical change.
Explanation:
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