Answer:
the open bag allowed the gas from the reaction to escape
Answer:
9 days, or 3 half-lives
Explanation:
5.2x10^5=520000
6.5x10^4=65000
65000/520000=1/8, or 3 half-lives
3x3=9 days
I'm not the greatest at Chem but this seems more like math than Chem :)
The answer is A. The element is sodium (Na) and is highly reactive