Concept explainers
(a)
Interpretation:
The
Concept introduction;
Atomic number (Z):
Atomic number of an element is the number of protons or the number of electrons found in the nucleus of every atom of that element.
Mass number (A):
Mass number of an element is defined as the total number of protons and neutrons in an atom.
Protons:
A proton is one of three main particles that make up the atom. Protons are a tiny, dense region at the center of the atom. Protons have a positive electrical charge of
Neutrons:
Atoms of all elements except for most atoms of hydrogen have neutrons in their nucleus. Unlike protons and electrons, which are electrically charged, neutrons have no charge they are electrically neutral.
Electrons:
Electrons have an electric charge of
(a)
Explanation of Solution
Given,
The atomic number is
The mass number is
An element with atomic number
Thus, the number of protons in the atom is
Thus, the number of electrons in the atom is
The number of neutrons can be calculated as,
The number of neutrons in an atom is
(b)
Interpretation:
The element symbol, element name, number of protons, number of electrons and the number of neutrons of an element with atomic number 13 has to be given.
Concept Introduction:
Refer to part (a).
(b)
Explanation of Solution
Given,
The atomic number is
The mass number is
An element with atomic number
Thus, the number of protons in the atom is
Thus, the number of electrons in the atom is
The number of neutrons can be calculated as,
The number of neutrons in an atom is
(c)
Interpretation:
The element symbol, element name, number of protons, number of electrons and the number of neutrons of an element with atomic number 38 has to be given.
Concept Introduction:
Refer to part (a).
(c)
Explanation of Solution
Given,
The atomic number is
The mass number is
An element with atomic number
Thus, the number of protons in the atom is
Thus, the number of electrons in the atom is
The number of neutrons can be calculated as,
The number of neutrons in an atom is
(d)
Interpretation:
The element symbol, element name, number of protons, number of electrons and the number of neutrons of an element with atomic number 55 has to be given.
Concept Introduction:
Refer to part (a).
(d)
Explanation of Solution
Given,
The atomic number is
The mass number is
An element with atomic number
Thus, the number of protons in the atom is
Thus, the number of electrons in the atom is
The number of neutrons can be calculated as,
The number of neutrons in an atom is
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Chapter 2 Solutions
Principles of General, Organic, Biological Chemistry
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