Question

Melting points of four solids A,B,C and D are 78 degree Celsius, 262 degree Celsius, 100 degree Celsius and 168 degree Celsius. Arrange them in the decreasing order of their inter particle force of attraction

Answer 1

Given conditions ⇒

Melting Point of A = 78° C
Melting Point of B = 262° C
Melting Point of C = 100° C
Melting Point of D = 168° C


We know, Melting point of the solids are directly proportional to the force of the attraction between its molecules.

∴ Solids having the high force of the attraction between its molecules = Solids having the High melting Point = B

In Descending Order,
B > D > C > A


Hope it helps.

Answer 2

Answer is B > D > C > A

Melting Point of the Solids are directly Proportional to the Force of the attraction between the molecules of the solids. 

Therefore, 
 Melting Point of Solids ∝ Inter particle Force of Attraction.


Now, Let us arrange that in the Descending Order,
B has the Highest melting Point, therefore it will be arranged first. After B, D have the High melting point, then  C and in last A.

Hence, it will be arranged in the given manner, 
   B > D > C > A


I hope it helps you.