Apiece of charcoal used for cooking is found at the remains of an ancient campsite. a 0.94 kg sample of carbon from the wood has an activity of 1580 decays per minute. find the age of the charcoal. living material has an activity of 15 decays/minute per gram of carbon present and the half-life of 14c is 5730 y. answer

Mass of sample of charcoal = 0.94 kg = 0.00094 

∴, activity = decay rate / mass = 1580/0.00094
                                                 = 1.681 X 10^6 decays per min per gram

Using the half-life formula, we have: 
activity of sample / activity of modern carbon = (1/2)^(age / half-life) 
∴, Age = half-life x log (base 2) (modern activity / coal activity)
           = 5730 x log(base 2)(1.681X10^6/ 15)
           = 96115 years.

Age of the charcoal = 96115 years

d

Explanation:

Approx. 70%

Explanation:

%Carbon

 

=

 

Mass of carbon

Mass of molecule

 

×

100

%

=

 

17

×

12.011

⋅

g

⋅

m

o

l

−

1

303.39

⋅

g

⋅

m

o

l

−

1

 

×

100

%

 

=

 

?

?

%