A compound contains 0.64g of copper, 0.32g of sulfur and 0.64g of oxygen .calculate its empirical formula

257 grams h2o i think

Answer earth,water,fire and air;

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.

It is a ok  i know i have a brain functioning well.