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.
Explanation:
Adhesion means the ability to stick on the surface of another substance.
Water exhibits adhesive forces due to which it is able to stick to the glass. Due to adhesive forces water spreads over the surface of glass and sticks to it.
These adhesive forces between the glass and water enough that it deforms the spherical shape of water molecules and help them stick to the surface of glass. As a result, adhesive forces overcome the repulsion between like molecules.
Hence, water is able to “stick” to the side of glass due to strong adhesive forces.
The answer should be false. Elements contain only one atom.
Ca(s)+2Hcl(aq) ------>CaCl2(s)+H2(g)