The answer would be C.
The salt and the water have both undergone physical changes.
Hope this helps!
Answer:
CH2O is formaldehyde a covalent compound and its intermolecular forces are week
KCl is an ionic compound formed by electrostatic force of attraction between positive and negative charge. Ionic compounds also exists in three dimensional crystal lattic that is why intermolecular forces in KCl is stronger.
Moreover melting point of KCl is higher than CH2O
Explanation:
Stored mechanical energy is energy stored and awaiting to be used and mechanical energy is the energy that was stored being used.
The solution before dilution and after dilution contains same number of moles, and water is added for dilution.
Option B
<h3><u>Explanation:</u></h3>
Suppose before dilution, the solution contains x moles of KCl in Y liter of water. Now as the concentration got halved, then the solution contains x moles of KCl in 2Y kiters of solution. So the number of moles of KCl in the solution remained constant.
Again, as the solution is diluted to half of the concentration, water must have been added with the solution to make it dilute.