Answer:
17202.6 years
Explanation:
Activity of the living sample (Ao) = 160 counts per minute
Activity of the wood sample (A) = 20 counts per minute
Half life of carbon-14 = 5730 years
t= age of the artifact
From;
0.693/t1/2= 2.303/t log Ao/A
Then;
0.693/ 5730= 2.303/t log Ao/A
Substituting values;
0.693/5730= 2.303/t log (160/20)
Then we obtain;
1.209×10^-4 = 2.0798/t
t= 2.0798/1.209×10^-4
Thus;
t= 17202.6 years
Therefore the artifact is 17202.6 years old.
Answer:
I am sure it is D or C. have a nice day
Answer:
The exposed metal rusts is an example of a chemical change because rust is an example of a chemical change in objects for example bicycles, scooters, etc.
Every electron carries one elementary negative charge. Concerning mass,
it takes roughly 1,840 electrons to make enough mass for 1 proton or 1 neutron.
Electrons don't necessarily have to stay connected to an atom, but when they do,
they circle the nucleus.
So you should select (C): ==> Negative, ==> light, ==> circling the nucleus.
Phosphorus tribromide is a covalent compound because they share electron pairs.