What is the molality of a solution of naphthalene dissolved in chloroform if the solution has a freezing point of -64.7 °C? ​

we know that 10 g of naphthalene is added to a test tube.  We determined and the cooling curve above that the freezing point of naphthalene is approximately 80.5  degreesC  .  We then add 1.1  g   of p-dichlorobenzene to the test tube.

Explanation:

atomic mass = 39

number of neutrons = 20

number of protons= 19

electronic configuration = 1s2 2s2 2p6 3s2 3p6 4s1

the number of electron in first shell = 2

number of electrons in n=3 shell = 8