Answer:
d
Explanation:
Isomers are molecules that have the same molecular formula(the same number of each atom), but different structural formulas
in this case both have the formula C2H5O
Group 1 contains metals while group 18 contains noble gases.
So group 1 is different from group 18 as they both contains different types of atoms as group 1 contains metals while group 18 contains noble gases.
There is 1 valence shell electron in group 1 , they are highly reactive while valence shell of group 18 is fully filled and they are least reactive .
No, they both refer to the ratio of moles in compounds of a chemical reaction. Along with mole ratio and molar ratio, this can also be called the mole-to-mole ratio.
Hope this helped :)