Shelter, you need a place to live
Answer:
There is one single covalent bond between two carbon atoms.
Explanation:
We know that sharing of electrons form covalent bonds.
If we look upon K,L,M ,N shells of the carbon and hydrogen atoms.
We found that Hydrogen is having only
electron in K shell.
And Carbon on the other hand is having
electrons in K shell and
electrons in L shell.
So carbon have
valence electrons,and it can share
bonds with any relevant atom to complete its octet.
And Hydrogen requires
electron to complete its doublet.
Alkane general formula 
For ethane 

Carbon atom is shared by
Hydrogen.
The remaining one electron
of carbon will be shared with another carbon atom.
An image of the sharing of electrons attached below,
Hence we have only
covalent bond between the two.
Answer:
0.6749 M is the concentration of B after 50 minutes.
Explanation:
A → B
Half life of the reaction = 
Rate constant of the reaction = k
For first order reaction, half life and half life are related by:


Initial concentration of A = ![[A]_o=0.900 M](https://tex.z-dn.net/?f=%5BA%5D_o%3D0.900%20M)
Final concentration of A after 50 minutes = ![[A]=?](https://tex.z-dn.net/?f=%5BA%5D%3D%3F)
t = 50 minute
![[A]=[A]_o\times e^{-kt}](https://tex.z-dn.net/?f=%5BA%5D%3D%5BA%5D_o%5Ctimes%20e%5E%7B-kt%7D)
![[A]=0.900 M\times e^{-0.02772 min^{-1}\times 50 minutes}](https://tex.z-dn.net/?f=%5BA%5D%3D0.900%20M%5Ctimes%20e%5E%7B-0.02772%20min%5E%7B-1%7D%5Ctimes%2050%20minutes%7D)
[A] = 0.2251 M
The concentration of A after 50 minutes = 0.2251 M
The concentration of B after 50 minutes = 0.900 M - 0.2251 M = 0.6749 M
0.6749 M is the concentration of B after 50 minutes.
Incomplete question. Full question reads;
Darwin developed the theory of evolution to explain why there are so many different kinds of living things. He could easily observe that offspring of any animals were slightly different from their parents and that this could allow for big changes over thousands of years. He did not know that genes caused the differences. Genes are now very important in the modern theory of evolution.
What most likely led to a change in the widely accepted theory of evolution?
Answer:
<u>new experiments involving genes and evolution </u>
<u>Explanation:</u>
Indeed, the original theory of evolution has experienced several changes in its acceptance because of its imperfect and wrong assumptions not based on generally acceptable scientific facts,
Hence, new experiments involving genes and evolution has led to a change (disagreements and few agreements) in the widely accepted theory of evolution.
The heat energy breaks down the bonds between the molecules of the solid so the molecules become looser. Further hearing of the liquid causes the bonds to be broken down and the molecules will move further apart.