Arrange the following elements in the increasing order of their metallic character Mg, Ca, K, Ge, Ga.

Explanation

Arrangement the given elements into different groups and periods in order of their increasing atomic numbers. So, we have
`{:("Group number",1,2,13,14),("Third period :",-,Mg,-,-),("Fourth period :",K,Ca,Ga,Ge):}`
Since, the metallic character decreases along a period from left to right, therefore, metallic character increase in the order : `Ge lt Ga lt Ca lt K` (as all these belong to same period). Now we compare the metallic character of Ca and Mg. Since, metallic character increases down the group from top to bottom, therefore, Ca is more metallic than Mg. Combining the above two results, the overall metallic character increase in the order `Ge lt Ga lt Mg lt Ca lt K`.