SCIENCE
CHEMISTRY
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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electrons
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occupied energy levels or shells
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electrons in the highest occupied energy level or outer shell
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None of the above
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Detailed explanation-1: -The elements in each group have the same number of electrons in the outer orbital. Those outer electrons are also called valence electrons. They are the electrons involved in chemical bonds with other elements. Every element in the first column i.e. group one has one electron in its outer shell.
Detailed explanation-2: -Assertion: Elements with the same chemical properties are kept in the same group. Reason: Elements in a group have the same number of electrons in the outermost shell hence they have similar chemical properties.
Detailed explanation-3: -Elements in each period have the same number of electron shells as the number of that period. Hydrogen and helium are in period 1, and both have one electron shell. Carbon, nitrogen and oxygen are all in period 2, and all have two electron shells. And so on.
Detailed explanation-4: -All the elements in the same group of the modern periodic table have the same number of valence electrons.
Detailed explanation-5: -Valence electrons are the electrons in the highest occupied principal energy level of an atom.