Fast ? ? an isotope of chlorine has a half life of 55.5 minutes. if we start with 45 kilograms of this isotope, how much will remain after 3.7 hours?

 The  amount   that will remain after 3.7  hours  for isotope  chlorine that has a half  life   of 55.5  minutes  is 2.813  kg

 Explanation

Half  life  is the  time required for the  radio activity  of  a specified isotope  to  fall  to  a  half its  original value.

convert 3.7  hrs  into  minutes

= 3.7  x 60 = 222 minute

 find the number of half life  that chlorine  isotope undergo   in  222  minutes

=222  minutes /  55.5   minutes = 4  half life

therefore   45 kg after first half life  =45 kg /2=22 .5 kg

                  22.5  kg after second  half life =  22.5/2 =11.25  kg

                 11.25  kg after third half life  = 11.25/2 = 5.625 kg

                5.625  kg  after  fourth  half life =  5.625/2 = 2.813 kg

surface mining destroys mountain tops, landscapes, forests and wildlife habitats. on top of that, it leads to soil erosion and destruction of agricultural land. the landscape changes can also disrupt river channels and streams, which leads to flooding. which, can destroy plant life and other animals as well.

explanation:

when atoms of different types of elements join together, they make molecules called compounds. water consists of compound molecules made up of 2 hydrogen atoms and 1 oxygen atom. this is why it's called h2o. water will always have 2 times the number of hydrogen atoms as oxygen atoms.