Half life question?

Question

A 50. mg sample of iodine -131 was placed in a container 32.4 days ago. If its half-life is 8.1 days, how many milligrams of iodine131 are now present?

Answer 1

In 8.1 days 50/2 = 25 mg left.

In 2 x 8.1 = 16.2 days 25/2 = 12.5 mg left.

In 3 x 8.1 = 24.3 days 12.5/2 = 6.25 g left

in 4 x 8.1 = 32.4 days 6.25/2 = 3.125 g left

So 3.125 g of iodine 131 are present.

Answer 2

There are now 3.125 mg of Iodine -131 according to that information. Half-Life is the amount of time it takes for a substance to lose half of its radioactivity.

Answer 3

There is 3 1/8 g left. 1/2 decomposes each 8.1 days.

Answer 4

the unique 0.5-life happens at a distant civilian and militia laboratory called the Black Mesa examine Facility. in the process an test, researchers at Black Mesa by threat reason a "resonance cascade" which rips open a portal to an alien international, Xen. Creatures from Xen flood into Black Mesa via the portal and initiate off killing each physique in sight. The participant takes on the region of Gordon Freeman, between the examine scientists who were in contact in the twist of destiny and who now could get away the ability. on the top of the sport, a mysterious discern colloquially universal because of the fact the G-guy extracts Gordon from Black Mesa and "promises" him employment. Gordon is consequently positioned into stasis.[26] In 0.5-life 2, the story resumes with the G-guy taking Freeman out of stasis and putting him right into a prepare en direction to city 17 an indeterminate style of years after the Black Mesa incident. genuine components variety on the actual length of this intermission. a narrative fragment written by making use of author Marc Laidlaw for the form group places the intermission at ten years,[27] on an analogous time as 0.5-life 2: Episode One's internet site places this intermission as "just about 2 many years" after the top of the activities of 0.5-life.[28] The environments in 0.5-life 2, in accordance with the sport's tale, all have a unique submit-apocalyptic topic, yet in layout they're multiple, and contain the jap eu-styled city 17, the zombie-infested Ravenholm; the coastal Nova Prospekt detention center and the large integrate fort. Viktor Antonov, the paintings director of 0.5-life 2, who spent his teenagers in Bulgaria, wrote that the builders consciously modeled 0.5-life 2's putting on jap Europe because of the fact they have been curious approximately making use of the region's mix of the two new and previous shape and wanted to infuse city 17 and its environs with an analogous experience of history.

Answer 5

the substance will loose 50% of it's weight every half live
there fore in 32.4days/8.1days = 4 half lives
1->1/2->1/4->1/8->1/16
1/16*50mg = 3.125mg

Answer 6

3.125mg

24.3 days ago-25mg left
16.2 days ago-12.5mg left
8.1 days ago-6.25mg left
now-3.125mg left