What to describe there's no picture
This n that description
they are pronouns,n they are a part of grammer
Answer: 100 grams of the parent isotope will remain after one half life.
Explanation:
Mass of the isotope present at initial stage = 
The mass of the parent isotope left after the time ,t=N
Time taken by the samle ,t = 
The half life of the sample :
![\ln[N]=ln[N^o]-\frac{0.693}{t_{\frac{1}{2}}}\times t_{\frac{1}{2}}](https://tex.z-dn.net/?f=%5Cln%5BN%5D%3Dln%5BN%5Eo%5D-%5Cfrac%7B0.693%7D%7Bt_%7B%5Cfrac%7B1%7D%7B2%7D%7D%7D%5Ctimes%20t_%7B%5Cfrac%7B1%7D%7B2%7D%7D)
![2=\frac{[N_o]}{[N]}](https://tex.z-dn.net/?f=2%3D%5Cfrac%7B%5BN_o%5D%7D%7B%5BN%5D%7D)
![[N]=\frac{N_o}{2}=\frac{200 g}{2}=100 g](https://tex.z-dn.net/?f=%5BN%5D%3D%5Cfrac%7BN_o%7D%7B2%7D%3D%5Cfrac%7B200%20g%7D%7B2%7D%3D100%20g)
100 grams of the parent isotope will remain after one half life.
Chage identity of a substance
he answer is because <span>samples of air taken over erupting volcanoes shows that volcanoes
contribute a small amount of chlorine in the stratosphere compared to CFCs. Volcanic
eruptions account for a large instability of chlorine from land to the
atmosphere on a yearly basis. This is in addition to chlorine that enters the
atmosphere from sea spray, industrial processes and biological gases which are
from CFCs. All of these inputs happen near or at the base of the atmosphere. Very
little of the material emitted from volcanoes makes it up into the upper
reaches of our atmosphere which is the stratosphere where it could touch the
ozone layer. However, most of it is believed to be deposited lower down which
is in the troposphere, where it then rained out back to the surface of the
earth.</span>
