Answer:
18 grams
Explanation:
Because 17,190 yrs divided by the amount of years it takes for a half-life to occur is 3. So 3 half life’s happen, so you divide 144/2 once, equaling 72. You divide 72/2 again (another half-life) and you get 36. You then calculate the third half life by dividing 36/2 which equals 18 grams.
767.448 Joules of heat is required.
You use the equation Q=MCdeltaT
Make sure you convery celsius to Kelvin
Specific heat of water is 4.18
So it will be Q=2.55(4.18)(72)
Q=767.448