Carbon-14 has a half-life of 5720 years and this is a first order reaction. if a piece of wood has converted 75% of the carbon-14, how old is it?
a. 11440 years
b. 2345 years
c. 4750 years
d. 4290 years
e. 1430 years

The characteristics of two different types of reactions are shown below: reaction a: electrons are gained by the atoms of an element. reaction b: protons are lost by the atom of an element. which statement is true about the atoms of the elements that participate in the two reactions? their identity changes in both reaction a and reaction b. their identity changes in reaction a but not in reaction b. their identity changes in reaction b but not in reaction a. their identity remains the same in both reaction a and reaction b.