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Answer:
<u><em>The aufbau principle</em></u>
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<u><em>The Pauli exclusion principle</em></u>
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<u><em>Hund's rule of maximum multiplicity</em></u>
Explanation:
<u><em>The aufbau principle:</em></u>
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The fundamental electronic configuration is achieved by placing the electrons one by one in the different orbitals available for the atom, which are arranged in increasing order of energy.
<u><em>The Pauli exclusion principle:</em></u>
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Two electrons of the same atom cannot have their four equal quantum numbers. Because each orbital is defined by the quantum numbers n, l, and m, there are only two possibilities ms = -1/2 and ms = +1/2, which physically reflects that each orbital can contain a maximum of two electrons, having opposite spins
<u><em>Hund's rule of maximum multiplicity:</em></u>
This rule says that when there are several electrons occupying degenerate orbitals, of equal energy, they will do so in different orbitals and with parallel spins, whenever this is possible. Because electrons repel each other, the minimum energy configuration is one that has electrons as far away as possible from each other, and that is why they are distributed separately before two electrons occupy the same orbital.
Answer:
Speed of river is 0.45 m/s
Speed of boat is 2.65 m/s
Explanation:
= Speed of river
= Speed of canoe
Adding the equations we get
Speed of river is 0.45 m/s
Speed of boat is 2.65 m/s
Force and Gravity, is what i think it is.
Answer:
Spring constant, k = 0.3 N/m
Explanation:
It is given that,
Force acting on DNA molecule, 
The molecule got stretched by 5 nm, 
Let k is the spring constant of that DNA molecule. It can be calculated using the Hooke's law. It says that the force acting on the spring is directly proportional to the distance as :
k = 0.3 N/m
So, the spring constant of the DNA molecule is 0.3 N/m. Hence, this is the required solution.
Answer:
a. Stars all warm objects
c. Some unstable atomic nuclei
Explanation:
Gamma rays are photons of very high energy (beyond 100keV) enough to remove an electron from its orbit.
They have a very short wavelength, less than 5 meters from the peak, and can be produced by nuclear decay, especially in the breasts of massive stars at the end of life.
They were discovered by the French chemist Paul Villard (1860 to 1934).
While X-rays are produced by electronic transitions in general caused by the collision of an electron with an atom at high speed, gamma rays are produced by nuclear transitions.
Gamma rays produce damage similar to those caused by X-rays or ultraviolet rays (burns, cancer and genetic mutations).
The sources of gamma rays that we observe in the universe come from <u>massive stars (hypernovas) or some warm objects on the space</u> that end their lives by a gravitational collapse that leads to the formation of a neutron star or a black hole, as well as <u>unstable radioactive nuclei </u>that emit radiation gamma to reach its steady state.
