After the first 2 min the 20 g are only 10g, (1 half-life)
after other 2 more min 5g (2 half-lives)
after other 2 more min 2.5 g (3 half-lives)
after 2 more 1.25 g (4 haf lifes)
2 atome nitrogen , 1 is correct
How likely and forcefully a substance reacts with oxygen, water, acids and other salts
