How is an element's most likely oxidation state related to its valence electrons?
A. It indicates what energy level the valence electrons of that
element are in.
B. It indicates how many valence electrons have been lost by that
element.
c. It indicates how many valence electrons the element has.
D. It indicates how many electrons are required to complete a full
valence shell

Electrons are emitted

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.