Answer:
Electron: A negatively charged particle found circling or orbiting an atomic nucleus. An electron, like a proton is a charged particle, although opposite in sign, but unlike a proton, an electron has negligible atomic mass. Electrons contribute no atomic mass units to the total atomic weight of an atom.
Explanation:
Data:
n (number of mols) = ?
V (volume) = 2.50 Liters
If:
1 L → 1000 g
2.50 L → y
y = 1000*2.50 = 2500 g
Therefore:
m (mass) = 2500 g
Now:
Molar Mass (MM) of oxygen = 16 g/mol
Formula:

Solving:


I belive it is synaptic cleft
Water is a polar solvent. Since, 'Like dissolves like' a polar compound will be most soluble in water whereas a non-polar compound will be the least soluble.
The increasing order of polarity for the given organic compounds is:-
CH3OCH3 < CH3NH2 < CH3CHO < CH3CH2OH
Ether is the least polar and hence least soluble in water.