FAST WILL GIVE BRAINLIEST!!! Read the information about the halogen family. Elements within a group share similar properties. Elements in the halogen family, such as fluorine (F), chlorine (Cl), bromine (Br), and iodine (I), all have seven valence electrons. Iodine is an important element for human health. The thyroid gland uses iodine to produce hormones. One of the hormones it makes is a covalent compound called thyroxine, which is shown in the image. Given this information, what effect do you think other halogen elements have on human health? State your prediction, and do some research on one of the halogen elements to see how it affects human health. List your findings, and then give your opinion on whether you think the element you chose should be used in food products, cleaning products, or in other manners that cause it to come in contact with humans. Be sure to provide evidence from your research to support your opinion.

part 1: the half-life of the element is 22 years.

part 2: it will take 132.02 year for the sample to decay from 308.0 g to 4.8125 g.

explanation:

part 1: there are two ways to determine the half life time.

first way: the half life time can be determined directly from its definition as it is the time required for the sample to decay to its half concentration.

from the data the initial concentration was 45.0 g and decayed to its half value (22.5 g) in 22.0 years.

second way: the radio active decay is considered first order reaction so we can use the laws of first order reactions.

k = (1/t) ln (a/a-x), where k is the rate constant of the reaction,

t is the time of the reaction

a is the initial concentration of the reactant

a-x is the remaining concentration at time (t)

a = 45.0 g the initial concentration at t = 0 year.

at t = 22 year, a-x = 22.5 g

then k = (1/22 year) ln (45.0 g/ 22.5 g) = 0.0315 year-1.

the half-life time (t1/2) = ln 2/ k = 0.693/ k =0.693/ 0.0315 = 22 years.

part 2:

using the same law k = (1/t) ln (a/a-x),

using the given data; a = 308.0 g and a-x = 4.8125 g and the calculated k from the part 1 (k = 0.0315 year-1)

t = (1/k) ln (a/a-x) = (1/0.0315) ln (308.0/ 4.8125) = 132.02 years

c- cold periods in earth's history during which glaciers covered much of the surface.

explanation: