[b]Recall the half-life of a substance is defined to be the amount of time it takes for half of ANY AMOUNT of that substance to decay. [br][br][/b]This applet illustrates that [color=#1e84cc][b]the half-life of an substance[/b][/color] is INDEPENDENT OF (i.e. DOES NOT DEPEND UPON) [color=#980000][b]the INITIAL AMOUNT of SUBSTANCE[/b][/color]. Thus, [color=#e06666][b]at any point in time[/b][/color], the [color=#1e84cc][b]half-life of a substance always remains invariant. [/b][/color][br][br]To illustrate this, [color=#e06666][b]move the pink point anywhere you'd like[/b][/color] and then slide the black slider. [br][br]