The heat of fusion of dichloromethane (CH2Cl2) is 6.2 kJ/mol.
Calculate the change in entropy Δs when 345 g of dichloromethane freezes at -95.1 °C.
Be sure your answer contains a unit symbol and the correct number of significant digits.

Answer : The entropy change of the dichloromethane is 142 J/K

Explanation :

To calculate the number of moles, we use the equation:

Given mass of dichloromethane = 345 g

Molar mass of dichloromethane = 84.93 g/mol

Putting values in above equation, we get:

To calculate the entropy change for different phase at same temperature, we use the equation:

where,  

= Entropy change  = ?

n = moles of dichloromethane = 4.06 moles

= enthalpy of fusion = 6.2 kJ/mol = 6200 J/mol   (Conversion factor:  1 kJ = 1000 J)

T = temperature of the system =

Putting values in above equation, we get:

Hence, the entropy change of the dichloromethane is 142 J/K

for step 7 table c on the lab "newtons law of action"   the average time it took the car to travel .25 meters   was 1.92 seconds.

the average time it took the car to travel 0.50 meters was 2.61 seconds

hope this : )