Thorium-227 has a half-life of about 19 days. How much of a 500 g sample of Thorium will remain un-decayed in 19 days?

i'm assuming that the correct answer is indeed the first one/ "a"..

it would be d. henry moseley

hope this !

and sorry if i'm late. have a good rest of your day! : d

answeridentity;

a. the law of proportion states the combination of 2 atoms in a specific ratio to produce multiple compounds such as the given statement of question ‘1st compound contains 88.8 % cu ’ indicates 88.8 g of cu is present along with 11.2 g oxygen in 100 g of compound whereas the statement ‘2st compound contains 79.9 % cu ’ indicates 79.9 g of cu is present along with 20.1 g oxygen in 100 g of compound

1st compound contains 88.8 g cu

for cu

m = 63 g /mol

atomic % = 88.8 /63 = 1.42

for o

m = 16 g /mol

atomic % = 11.2 /16 = 0.7

b. the emperical formula of 1st compound is

cu1.4o0.7

cu2o