Hydrogen + oxygen --> water
2,1g + 16,8g = x
x = 18,9g

Actually Welcome to the concept of Bond Formation.
Answer is :-
B.) O and Cl
These both are Non-Metals with high Electronegativity nature, hence none of them can share electrons to foram any bond to eventually form a Electro valentines Compound.
If a molecule has four hybrid sp3 orbitals, it can be concluded that the molecule has a TETRAHEDRAL GEOMETORY
Answer:
144.12873
Explanation:
Hope this helps you
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回答:
144.12873
説明:
これがお役に立てば幸いです