Answer:
The right answer is "3 g".
Explanation:
Given:
Initial mass substance,

By using the relation between half lives and amount of substances will be:
⇒ 


Thus, the above is the correct answer.
Silver is not a compound. It's a mixture
The one with higher mass has a higher density because it fits more mass into the same amount of space (volume).
the branch of science that deals with the identification of the substances of which matter is composed; the investigation of their properties and the ways in which they interact, combine, and change; and the use of these processes to form new substances.the branch of science that deals with the identification of the substances of which matter is composed; the investigation of their properties and the ways in which they interact, combine, and change; and the use of these processes to form new substances.