The correct order of melting points of the following salts is:
LiCl & (I)
LiF & (II)
LiBr & (III)
Step 1: Ionic Compound Melting Point Determinants
Melting point is governed by: 1. Lattice Energy: Greater lattice energy correlates with a higher melting point. 2. Anion Size: Smaller anions result in increased lattice energy.
Step 2: Salt Analysis
Anion size order: Fluoride (F$^-$)<Chloride (Cl$^-$)<Bromide (Br$^-$).
Lattice energy order: \[ LiF>LiCl>LiBr \] Melting point follows lattice energy: \[ LiF>LiCl>LiBr \]
Step 3: Conclusion
Therefore, the melting point order is: \[ {\(LiF (II)>LiCl (I)>LiBr (III)\)} \] This corresponds to option (B).
A particle is moving in a straight line. The variation of position $ x $ as a function of time $ t $ is given as:
$ x = t^3 - 6t^2 + 20t + 15 $.
The velocity of the body when its acceleration becomes zero is: