Which pair of ions can form an ionic bond with watch other and why

An ionic bond is a bond between a non-metal and a metal. An example of an ionic bond is NaCl (sodium chloride or table salt). Na+ (sodium) is a metal, while Cl- (chloride) is a non-metal. Another example of an ionic bond is BaS (barium sulfide). Ba+ is a metal while S- is a nonmetal.

Particle exchange energy though elastic collision , hope this .

Radon-222 or rn-222 has a half-life of 3.82 days. to determine the fraction of an original sample of rn-222 that remains unchanged after 7.646 days, we calculate the amount of rn-222 remaining after 7.646 days and divide it with the original amount. using 1 gram as a basis and using half-life calculation methods, we can determine that  0.249 or 0.25  grams of rn-222 will remain, and thus the fraction remaining is 0.25 or 1/4.