From the following elements:_ 4 Be;_ 9 F;_ 19 K;_ 20 Ca; 1. Selec… - Vidyadip

Question

From the following elements:$_{4}\text{Be};_{9}\text{F};_{19}\text{K};_{20}\text{Ca};$

Select the element having one electron in the outermost shell.
Two elements of the same group.

Write the formula of and mention the nature of the compound formed by the union of ${ }_{19} K$ and element $X(2,8,7)$.

✓

Answer

19 K has one electron in its outermost shell.
4 Be and 9 F r elements belonging to the same group.

X(2, 8, 7) is chlorine and the element formed by 19K and 17Cl is KCl and the nature of the compound is ionic.

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