chemistry
posted by Eddy .
A 1.00g sample of carbon from a modern
source gave 15.3 disintegrations per minute. A sample of carbon from an “old” source gave 920 disintegrations per hour. What is the age of the “old” sample of carbon? The halflife of carbon14 is 5.73×103 year.
a. about 34,400 years
b. about 345,000 years
c. about 20 million years
d. less than a few years

chemistry 
Eddy
Typo: The halflife is 5.7x10^3

chemistry 
drake
Without even doing the math it the change in disintegrations is merely .03333, the sample must have decayed for
d. less than a few years 
chemistry 
drake
whoops, i did the math and it came out to about 34,400 years. Sorry for my earlier answer

chemistrycan't get 34,000 yrs 
DrBob222
k = 0.693/t_{1/2}
k = 0.693/5.7E3 = 1.22E4
ln(15.3333/15.3) = 1.22E4(t)
t = about 18 year. 
chemistry 
Anonymous
vanden bout

chemistry 
mayra
actually drake was right on his first answer i had this question on my homework and it is d. less than a few years :)
Respond to this Question
Similar Questions

college geology dealing with carbon 14
ok in my professors notes he calculates carbon 14 age in an example. The problem goes like this: Sample contains 110g carbon sample produces 70 disintegrations per minute. That is 0.7 disintegrations per minute. T=(1/lambda)ln(N0/Nt) … 
college geology help please
I was the same person from yesterday. I need help on a question. I don't type very good so I have one of my host family do it for me. so please help us. Suppose you have a sample of clamshell at a Paleoindian site and you measure the … 
college Geol 101
Suppose you have a sample of clamshell at a Paleoindian site and you measure the 14C activity of a 100gram sample of carbon as 320 disintegrations per minute (or 3.2 disintegrations per gram of carbon per minute). a.What was the activity … 
chemistry
A 1.00g sample of carbon from a modern source gave 15.3 disintegrations per minute. A sample of carbon from an “old” source gave 920 disintegrations per hour. What is the age of the “old” sample of carbon? 
Chemistry
The cloth shroud from around a mummy is found to have a carbon14 activity of 8.1 disintegrations per minute per gram of carbon as compared with living organisms that undergo 15.2 disintegrations per minute per gram of carbon. From … 
ChemB
The activity of carbon 14 in living tissue is 15.3 disintegrations per minute per gram of carbon. The limit for reliable determination of age is based on carbon 14 is .10 disintegration per min per gram of carbon. Calculate the max … 
science
The halflife of carbon 14 is 5730 years. if a 1 g sample of old carbon is 1/8 as radioactive as 1 g of a current sample, then the age of the old sample is about ___________years. 22,900 17,200 11,500 716 
chem
I am not sure if there is an equation for this problem or wut? 
Radioactivity
1. A granite rock is thought to be about 2 billion years old. why is it not possible to determine the age of the Rock using carbon14 dating? 
Chemistry
An archeological artifact was subjected to radiocarbon dating. The artifact showed a carbon14 decay rate of 13.8 disintegrations/ min per gram of carbon. Carbon14 has a halflife of 5715 years, and currently living organisms decay …