A 22.5 g sample of X reacts with a sample of Y to form 68.3 g of XY. What is the mass of Y that reacted.

60.0 - there are 3 significant numbers

Answer///precipitate;

Answerthe same as;

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.