The number of grams of radon 222 did it have 15.2 ago was 49.6 grams( answer C)
<u>calculation</u>
- calculate the number of half life it has covered from 15.2 days to 3.8 days
that is divide 15.2/ 3.8 = 4 half life
- half life is time taken for a radio activity of a specified isotope to fall to half its original mass
therefore 3.8 days ago it was 3.1 x2 = 6.2 grams
7.6 days ago it was 6.2 x2 = 12.4 grams
11.4 days ago it was 12.4 x2= 24.8 grams
15.2 days ago it was 24.8 x2=49.6 grams
The other gas which the article mentioned is Helium gas.
<h3>What is Compression?</h3>
This refers to the squeezing or shortening of a substance which is most often done by increasing the temperature.
The information scientists hope to gain by compressing this gas into a solid is by studying the molecular structures and using it in the production of other substances which is why Nitrogen and Helium are the gases being studied in this scenario.
Read more about Compression here brainly.com/question/17266589
2NaOH=Na2O +H2O
The coefficient of NaOH is 2