What is the freezing point of a 0.05500 m aqueous solution of #NaNO_3#, if the molal freezing-point-depression constant of water is 1.86°C /m?

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Answer 1 · 2016-12-28T09:54:52

We know the depression of freezing point

#DeltaT_f=K_fxxbxxi#

Where

#K_f->"cryoscopic consrant"=1.86^@"C/m"#

#b->"molal concentration"=0.055m#

#i->"Van'tHoff factor"=2" for "NaNO_3 "*"#

#"*"# As #NaNO_3# dissociates as follows producing 2 ions per molecule.

#NaNO_3rightleftharpoonsNa^+ +NO_3^(-)#

So

#DeltaT_f=1.86xx0.055xx2~~0.2#

So the freezing point of the given aqueous solution will be #-0.2^@C#