The atomic number is a fundamental concept in chemistry and physics. It is a unique identifier for each element in the periodic table, indicating the number of protons in the nucleus of an atom. In this article, we will explore the definition and meaning of atomic number, its origin, associations, synonyms, antonyms, and example sentences.
Definitions
The atomic number is defined as the number of protons in the nucleus of an atom. It is represented by the symbol Z and is unique for each element. The atomic number determines the chemical properties of an element and its place in the periodic table.
Another definition of atomic number is the number of electrons in an atom, which is equal to the number of protons in a neutral atom. This definition is used in some contexts, such as in the calculation of electron configurations.
Origin
The concept of atomic number was first proposed by the British chemist Henry Moseley in 1913. Moseley discovered that the elements could be arranged in a more logical and consistent manner if they were ordered by their atomic number, rather than their atomic weight. This led to the modern periodic table, which is based on the atomic number of each element.
Meaning in different dictionaries
The atomic number is defined in various dictionaries as the number of protons in the nucleus of an atom. For example, the Oxford English Dictionary defines it as “the number of protons in the nucleus of an atom, which determines the chemical properties of the element.” Merriam-Webster defines it as “the number of protons in the nucleus of an atom that determines the chemical properties of an element.”
Associations
The atomic number is associated with the properties of elements, such as their chemical reactivity, electronegativity, and ionization energy. It is also used to determine the structure of atoms and molecules, as well as their electronic configurations.
Synonyms
Synonyms for atomic number include proton number, nuclear charge, and element number.
Antonyms
Antonyms for atomic number include atomic weight, atomic mass, and isotope number.
The same root words
The root words of atomic number are “atomic” and “number.” Atomic refers to the structure of atoms, while number refers to a numerical value.
Example Sentences
- The atomic number of carbon is 6, which means it has 6 protons in its nucleus.
- The periodic table is arranged by atomic number, with elements in the same group having similar properties.
- The atomic number of an element can be used to predict its chemical behavior.
- The atomic number of an element is always an integer, as it represents a whole number of protons.
- The atomic number of an element can be determined using a mass spectrometer.