Answer:
Because no two elements have the same set of energy levels, different elements emit different colors of light. Energy is released when electrons move from higher energy levels to lower ones (visible light).
Explanation:
Answer:
N- 1s2 2s2 2p3
Mg- 1s2 2s2 2p6 3s2
O- 1s2 2s2 2p4
F- 1s2 2s2 2p5
Al-1s2 2s2 2p6 3s2 3p1
Explanation:
Order of decreasing atomic radius
Mg,Al, N,O,F
Order of increasing ionization energy
Mg,Al, N,O,F
Reason:
Atomic radius decreases with increase in nonmetallic character. Looking at the electronic configurations, as effective nuclear charge increases, the atom becomes smaller and the attractive force between the nucleus and the outermost electrons increases. Hence, the radius of the atom decreases and ionization energy increases. Note that the addition of more orbital electrons implies addition of more nuclear charge since the both must exactly balance for the atom to remain electrically neutral. The more the electrons in the outermost shell, the higher the first ionization energy.
<u>Answer: </u>The correct statement is X is the effective nuclear charge, and it increases across a period.
<u>Explanation:</u>
We are given that:
X = number of protons − number of core electrons
Effective nuclear charge is defined as the actual nuclear charge (Z = number of protons) minus the screening effect caused by the electrons present between nucleus and valence electrons. These electrons are the core electrons.
The formula used for the calculation of effective nuclear charge given by Slater is:

where,
= effective nuclear charge
Z = atomic number or actual nuclear charge or number of protons
= Screening constant
The effective nuclear charge increases as we go from left to right in a period because nuclear charge increases with no effective increase in screening constant.
Hence, the correct answer is X is the effective nuclear charge, and it increases across a period.
Answer:The molar mass is the mass of a given chemical element or chemical compound (g) divided by the amount of substance (mol).
The molar mass of a compound can be calculated by adding the standard atomic masses (in g/mol) of the constituent atoms.
Explanation:
(If this is correct, can I have Brainlist?)
Answer:
D) anomalous volcanoes such as those in Hawaii