Question

in the modern periodic table element Calcium atomic number 28 surrounded by element with at Number 12 ,19 ,20 and 38 which of these element has physical and chemical properties resemble those of calcium and why.

Answer 1

element with atomic number 12 will resemble similat properties to that of calcium as they both lie in the same group and have Equal no. of valence electrons. Thus, they both will show similar properties .

Answer 2

but in modern periodic atomic number of calcium is 20..am i right?.. i think there is some mistake in your question