ATOMIC RADIUS Meaning and
Definition
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Atomic radius refers to the measurement of an atom from its nucleus to the outermost shell or orbit of its electrons. It is a fundamental concept used in the field of chemistry to describe the size of an atom. The atomic radius is primarily influenced by two factors: the number of electron shells and the effective nuclear charge.
The number of electron shells determines the overall size of an atom. As the number of electron shells increases, the atomic radius also increases. This is because with each additional electron shell, the atom's outermost electrons are located further from the positively charged nucleus, resulting in a larger atomic radius.
The effective nuclear charge refers to the attractive force exerted by the nucleus on the valence electrons. As the number of protons in the nucleus increases, the effective nuclear charge also increases. This causes the valence electrons to be pulled closer to the nucleus, resulting in a smaller atomic radius.
Atomic radius is an essential property as it impacts various chemical and physical characteristics, such as atomic volume, reactivity, and metallic behavior. With a larger atomic radius, atoms are more likely to form ionic bonds since they can readily lose or gain electrons to achieve a stable electron configuration. Conversely, smaller atomic radius atoms tend to form covalent bonds, sharing electrons to complete their valence shell.
In summary, atomic radius refers to the distance between an atom's nucleus and its outermost electron shell. It is influenced by both the number of electron shells and the effective nuclear charge, impacting an atom's size, reactivity, and bonding behavior.
Etymology of ATOMIC RADIUS
The etymology of the word "atomic radius" can be broken down as follows:
1. Atomic: The term "atomic" originates from the Greek word "atomos" which means "indivisible" or "uncuttable". It was introduced by the ancient Greek philosopher Democritus, who theorized that matter is composed of indivisible particles called atoms.
2. Radius: The term "radius" comes from the Latin word "radius" meaning "ray" or "spoke of a wheel". It refers to a straight line segment that joins the center of a circle or sphere to any point on its circumference.
Combining these origins, "atomic radius" refers to the distance from the nucleus of an atom to its outermost electron in terms of a circle or sphere. It indicates the size of an atom.
