Question

Which of the following atoms have a smaller atomic radius than Ca (calcium)?

a) Sr (38)
b) Ba (56)
c) K (19)
d) Ge (32)

Answer 1

The elements given in choices a, c, and d have an atomic radius smaller than that of Ca (calcium).

Sr, Ba and K have atomic radii of 194 pm, 270 pm and 200 pm respectively, while Ca has an atomic radius of 197 pm.

Ge has an atomic radius of 223 pm, so it is bigger than the atomic radius of Ca.