Heat can be absorbed or produced
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)
Magnesium is classified as a metal. Magnesium has two valence electrons
Potential : a yoyo before it’s been released
Kinetic : skateboarding
Answer:
Option b is correct.
Explanation:
When 
is dissolved in water, 
and 
are formed.
As is an weak base and is a strong acid, the resulting solution will be acidic in nature.
if K_b value is known, then pH of the solution can also be determined which will support prediction.
However, acidic and basic nature of the solution can be predicted without K_b value also.
So, among the given option, (b) is correct.
