It is a subscript
Also do you mean Cl not Ci. I assume you do because then it means 4 chlorine in that compound.
Answer:
The volume occupied by molecules becomes a significant part of the total volume.
Attractions between molecules cause a reduction in volume.
Explanation:
C is wrong. The masses of molecules are constant.
What does it happen in smallest scale?
<span>You have to look for "DUPRE' EQUATION" which treat about </span>
<span>"TWO-PHASE INTERFACIAL FORCEs". </span>
<span>At boundary surface between two aggregation phases, you may attribute upper energy level to molecules standing at the boundary zone. So, it has to define INTERFACIAL FORCEs WHICH ACT TO REMODEL SHAPE AND EXTENSION OF MEETING PHASEs. </span>
<span>In your case, Water's Droplet is a liquid phase surrounded by Air (e.g. gas phase) and Interfacial Forces act to dominate Boundary-Surface. </span>
<span>Mathematically, smallest possible Surface comes to SPHERICAL SHAPE. </span>
If you remove thermal heat from the reaction the reaction will slow down. meaning that there will be fewer collisions occurring between the particles.
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CuO+H2=Cu+H2O the equation is balanced.