2H2O(g) → 2H2(g) + O2(g) ΔH = +483.60 kJ/mol at a certain temperature. If the increase in volume is 47.7 L against an external pressure of 1.00 atm, calculate ΔU for this reaction. (The conversion factor is 1 L · atm = 101.3 J.)

radioactive decay occurs in unstable atomic nuclei – that is, ones that don't have enough binding energy to hold

the nucleus together due to an excess of either protons or neutrons.

c-14 is carbon-14, or radiocarbon.   it is a radioactive isotope of carbon with an atomic nucleus containing 6 protons and 8 neutrons.