In a periodic table periods are horizontal and groups are vertical. Horizontal is left to right and vertical is up and down.
Hope this helps!
I think it’s oxygen and carbon
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If the concentration of water inside a cell is higher than the concentration of water outside a cell, osmosis will take place, as water will move from an area of low solute concentration inside the cell to higher solute concentration, outside the cell.
Answer:
(2R,3S)-2-ethoxy-3-methylpentane
and
(2S,3S)-2-ethoxy-3-methylpentane
Explanation:
For this case, we will have 
as nucleophile. Also, this compound is also in excess. So, we will have as solvent 
a protic solvent. Therefore the Sn1 reaction would be favored.
The first step would be the carbocation formation followed by the attack of the nucleophile. In this case both isomers would be produced: R and S (see figure).
