What is the formula unit for a compound made from Li and Cl? (5 points) LiCl because the total negative charge on Cl is one.
LiCl because the total negative charge on Li is two.
Li2Cl because the total positive charge on Cl is one.
Li2Cl because the total positive charge on Li is two.

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.

Hcn is your answer my guy : )