Answer:-
A. A water molecule
Explanation:-
A molecule is the smallest particle of a compound that retains all it's chemical properties.
Here H2O is a compound. So the smallest particle that will retain all the chemical properties and still remain water is water molecule.
Atoms Hydrogen and Oxygen both have different chemical properties from water H2O and are thus different.
Hydrogen peroxide is different molecule from water. So it is also not water.
Yes, the atomic radius increases as you move down a group of elements.
this is true
going down leads to valence electrons that are further away from nucleus -> less electrostatic attraction -> less pull towards nuc. -> greater radius/volume taken
What was the question here?
The reaction is a displacement reaction. Iron is more reactive than copper. Hence, it displaces copper,forming iron II sulfate and copper metal.
This reaction is an exothermic reaction, hence it releases energy. The colour change indicates that iron has displaced copper.
