<u>Answer:</u> The tree was burned 16846.4 years ago to make the ancient charcoal
<u>Explanation:</u>
The equation used to calculate rate constant from given half life for first order kinetics:

where,
= half life of the reaction = 5715 years
Putting values in above equation, we get:

Rate law expression for first order kinetics is given by the equation:
![k=\frac{2.303}{t}\log\frac{[A_o]}{[A]}](https://tex.z-dn.net/?f=k%3D%5Cfrac%7B2.303%7D%7Bt%7D%5Clog%5Cfrac%7B%5BA_o%5D%7D%7B%5BA%5D%7D)
where,
k = rate constant = 
t = time taken for decay process = ? yr
= initial amount of the sample = 100 grams
[A] = amount left after decay process = 13 grams
Putting values in above equation, we get:

Hence, the tree was burned 16846.4 years ago to make the ancient charcoal
Answer:
The chemist can either:
a. Use a small fractionation apparatus.
b. Add a compound with a much higher boiling point.
Explanation:
Using a smaller fractionation apparatus or Vigreux column will help to minimize loss of the distillate.
If a compound with a higher boiling point is added, the vapors of this liquid will displace the vapors of this small amount of compound with a lower boiling point. This compound with a higher boiling point is known as a Chaser.
Answer:
=60 milligrams
Explanation:
12 x 5
=60 milligrams
Have a nice day!!!!!!! :-)
<u>KA</u>
Answer: 4Kcal
Explanation:
H= mcø
M=200g
C= 1 cal/g/°c
Ø= 40-20=20°c
H= 200*1*20= 4000calories= 4Kcal