Molecules do not have enough kinetic energy to overcome the intermolecular bonds.
I believe it is B. I’m sorry if i’m wrong. Tell me if i’m wrong or right!
Option (a) is correct.
A reducing agent is the one which loses electrons to other substance and an oxidizing agent is one which accepts electrons.
Here, In
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, Cr has oxidation number 6+ in the L.H.S of the equation, but on R.H.S its oxidation number is 0 i.e. it Cr has gained electrons such that total charge is 0.
And the oxidation state of Al in the left-hand side of equation is 0 and in right-hand side, it is +6.i.e. it has donated its electrons to Cr.
Hence, Cr is the oxidizing agent and Al is the reducing agent.
On a molecular level there is a lot of movement which in turn is the reason why heat is generated.