The half-life for radioactive decay of `""^(14)C` is 5730 yr. An archaeological artifact containing wood had only 80% of the `""^(14)C` found in a living tree. Calculate the age of the sample.

What is carbon dating ? Explain. In a sample of wood C-14 activity is 10% of the activity found in fresh wood. Calculate the age of wood sample. (t_1/2 for C-14 is 5760 years )

C-11 is a radioisotope of carbon. Its half life is 20 minutes. What fraction of the initial number of C-11 atoms in a sample will have decayed away after 80 minutes ?

The gas phase decomposition of dimethyl ether follows the first order kinetics as CH_3 - O - CH_(3) (g) to CH_(4) (g) + H_(2) (g) + CO(g) This reaction is carried out in a constant volume container at temperature of 500°C and has a half-life of 14.5 min. Initially, only dimethyl ether is present at a pressure of 0.40 atm. After 12 min, find the total pressure of the system. Assume ideal gas behaviour.