How long will the plant have been dead when 87.5 percent of its C-14 has become N-14? After 1 half-life After 2 half-lives After 3 half-lives After 4 half-lives
50
25
12.5
6.25
percent of 14C remaining

Iknow the answer to 13 is b and 14 is d. i just need to know why the correct answers are correct

Which formula can be used to calculate the molar mass of ammonia (nh3)? molar mass of n + molar mass of h 3 × molar mass of n + molar mass of h molar mass of n + 3 × molar mass of h 3 × molar mass of n + 3 × molar mass of h

The fact that the total amount of energy in a system remains constant is a(n)