$K$ and $Ca$ have atomic numbers $19$ and $20$ respectively,and they belong to the same period.
$(a)$ Which among them would have a smaller atomic size?
$(b)$ Which one would be more electropositive?
$(c)$ To which group would each of them belong?
$(a)$ Which among them would have a smaller atomic size?
$(b)$ Which one would be more electropositive?
$(c)$ To which group would each of them belong?
(N/A) $Ca$ has a smaller atomic size. As we move from left to right across a period,the atomic size decreases because the effective nuclear charge increases,pulling the electrons closer to the nucleus.
$(b)$ $K$ is more electropositive. Electropositive character (metallic character) decreases across a period from left to right because the effective nuclear charge increases,making it harder to lose electrons.
$(c)$ $K$ belongs to group $1$ (Alkali Metals). $Ca$ belongs to group $2$ (Alkaline Earth Metals).
$(b)$ $K$ is more electropositive. Electropositive character (metallic character) decreases across a period from left to right because the effective nuclear charge increases,making it harder to lose electrons.
$(c)$ $K$ belongs to group $1$ (Alkali Metals). $Ca$ belongs to group $2$ (Alkaline Earth Metals).
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Similar Questions
Three elements $X$,$Y$,and $Z$ have atomic numbers $7$,$8$,and $9$ respectively.
$(a)$ State their positions (Group number and period number both) in the Modern Periodic Table.
$(b)$ Arrange these elements in the decreasing order of their atomic radii.
$(c)$ Write the formula of the compound formed when $X$ combines with $Z$.
$(a)$ State their positions (Group number and period number both) in the Modern Periodic Table.
$(b)$ Arrange these elements in the decreasing order of their atomic radii.
$(c)$ Write the formula of the compound formed when $X$ combines with $Z$.
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View Solution$Li, Be, B$ and $C$ are the elements of the same period of the Modern Periodic Table.
$(a)$ Arrange them in increasing order of their atomic size.
$(b)$ In which shell (number) would the last electron enter for all of them?
$(c)$ Calculate the number of valence electrons in each.
$(d)$ Which element amongst them is most electropositive?
$(a)$ Arrange them in increasing order of their atomic size.
$(b)$ In which shell (number) would the last electron enter for all of them?
$(c)$ Calculate the number of valence electrons in each.
$(d)$ Which element amongst them is most electropositive?
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View SolutionList any two properties of the elements belonging to the first group of the modern periodic table.
Easy
View SolutionName:
$(a)$ three elements that have a single electron in their outermost shells.
$(b)$ two elements that have two electrons in their outermost shells.
$(c)$ three elements with filled outermost shells.
$(a)$ three elements that have a single electron in their outermost shells.
$(b)$ two elements that have two electrons in their outermost shells.
$(c)$ three elements with filled outermost shells.
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View Solution$(a)$ How does electropositivity of elements get affected as we move :
$(i)$ down a group
$(ii)$ across a period?
$(b)$ Which atomic property increases both as we move across a period or down a group?
$(i)$ down a group
$(ii)$ across a period?
$(b)$ Which atomic property increases both as we move across a period or down a group?
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