<u>Answer: </u>He sorted on the basis of average atomic weights.
<u>Explanation:</u>
Dmitri Mendeleev in 1863 arranged chemical elements in the groups according to their average atomic weights.
He said that elements which have similar chemical properties either have similar atomic weights or their atomic weights increases regularly.
Hence, he collaborated a great work in sorting the elements according to their average atomic weights.
Given :
A compound has a molar mass of 129 g/mol .
Empirical formula of compound is C₂H₅N .
To Find :
The molecular formula of the compound.
Solution :
Empirical mass of compound :
Now, n-factor is :
Multiplying each atom in the formula by 3 , we get :
Molecular Formula, C₆H₁₅N₃
Answer:
C is the answer to your question
the time it take for a planet to rotate on its axis makes up its day so if it were slower the day would be longer like earth, it take about 24 hours to make one full rotation.
Now for a year the distance from its star is the largest factor, because the further out the longer it takes to revolve around it, thus making a longer year.
The answer is (C) as the definitions states that atomic mass is the number of protons and neutrons.
Hope this helps :).
