Answer:
Radioactive isotopes ranging from 11O to 26O have also been characterized, all short-lived. The longest-lived radioisotope is 15O with a half-life of 122.24 seconds, while the shortest-lived isotope is 12O with a half-life of 580(30)×10−24 seconds (the half-life of the unbound 11O is still unknown).
<span> If you want to lift something that weighs
100kg, you have to pull down with a force equivalent to 100kg, which is
1000N (newtons). I hope this helps, please mark brainiest if it does. I will attach a picture I found off the internet to further help you :)
(There are like 1,000,000,000,000,000,000,000 other ways I could have put that, to make it sound less creepy, I could just edit it now instead of writing this huge thing... oh well lol)
</span>
Part (a):
Chalk has the chemical formula: CaCo₃
From the periodic table:
mass of Ca = 40 grams
mass of Co = 58.9 grams
Therefore:
molecular weight of chalk = 40 + 3(58.9) = 216.7 grams
Part (b):
Advantages of M<span>andeleev's periodic table:
1- Could predict the properties of elements easily based on its position in the periodic table
2- Elements were arranged systematically in order of increasing atomic mass which helped in the study and classification of elements
3- Even after the discovery of noble gases, no major changes needed to be done to the periodic table. Noble gases were inserted easily
4- He left room for other undiscovered elements based on his systematic approach in writing the table
Hope this helps :)</span>
This should increase the volume.
