Compound are formed by two or more elements chemically combined. For example: H^2O is the water formula, this is a compound because you two elements which are Hydrogen and Oxygen and together they form a compound. The (^2) is the amount of atoms the formula has, in this case Hydrogen has two atoms and Oxygen is neutral.
The correct letter to your answer would be A
The answer is mechanical wave!
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Ionization energy refers to the amount of energy needed to remove an electron from an atom. Ionization energy decreases as we go down a group. Ionization energy increases from left to right across the periodic table.
<h3>What is ionization energy?</h3>
Ionization is the process by which ions are formed by the gain or loss of an electron from an atom or molecule.
Ionization energy is defined as the energy required to remove the most loosely bound electron from a neutral gaseous atom.
When we move across a period from left to right then there occurs a decrease in atomic size of the atoms. Therefore, ionization energy increases along a period but decreases along a group.
Smaller is the size of an atom more will be the force of attraction between its protons and electrons. Hence, more amount of energy is required to remove an electron.
Thus, we can conclude that the energy required to remove an electron from a gaseous atom is called ionization energy.
Learn more about the ionization energy here:
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