Ethyne (c2  h2  (g),  hf  = 226.77 kj/mol) undergoes complete combustion in the presence of oxygen to produce carbon dioxide (co2  (g),  hf  = –393.5 kj/mol ) and water (h2  o(g),  hf  = –241.82 kj/mol) according to the equation below.what is the enthalpy of combustion (per mole) of c2  h2  (g)?     use  

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.

the correct option is c.

isotopes refers to different forms of the same element with the same atomic number but different mass number as a result of difference in their neutron numbers. isotopes have different relative atomic mass but share the same chemical properties.