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                        Solution boiling point

Solution boiling point hinges on its dissolved substance amenity yawns. If it dissolved substance more volatile than its dissolving (inferior dissolved substance boiling point), therefore solution boiling point becomes inferior of its dissolving boiling point or said by solution boiling point is down. Its example is ethyl alcohol solution in its boiling point water inferior of 100 °C but overbids of 78,3 °C (ethyl alcohol boiling point 78,3 °C and water boiling point 100 °C). If it dissolved substance don't volatile (are not volatile or nonvolatile ) than its dissolving (higher dissolved substance boiling point), therefore solution boiling point becomes to overbid from its dissolving boiling point or said by solution boiling point ascends. On ethyl alcohol solution example in that water, if looked on by its dissolving is ethyl alcohol, therefore solution boiling point also rise. Solution boiling point ascension because of descent of solution vapour pressure. Based jurisdictional koligatif's character solution, solution boiling point ascension of purification dissolving boiling point its straight equal with solution molality. 

Δ t _b = k _b . m

Δ t _b = solution boiling point ascension. 

k _b = molal's boiling point ascension dissolving. 

m = solution concentration in molal. 

Trifling example: 

Account glucose solution boiling point 0,1 m if molal's boiling point ascension waters 0,512 °C / m! 

Answer: 

Δ t _b = k _b . m = 0,512 °C / m x 0,1 m = 0,0512 °C

So t _b solution = t _b water + Δ t _b = 100 °C + 0,0512 °C = 100,0512 °C

c. Solution freezing point

Solution vapour pressure decrease cause solution freezing point becomes inferior of purification dissolving freezing point it. koligatif's character law to solution freezing point decrease applies on solution with volatile dissolved substance( volatile ) and also don't volatile( nonvolatile ). Based jurisdictional that, solution freezing point decrease of purification dissolving freezing point its straight equal with solution molality. 

Δ t _f = k _f . m

Δ t _f = solution freezing point decrease. 

k _f = molal's freezing point decrease dissolving. 

m = solution concentration in molal. 

Trifling example: 

Account glucose solution freezing point 0,1 m if penuruan molal's freezing points waters 1,86 °C / m! 

Answer: 

Δ t _f = k _f . m = 1,86 °C / m x 0,1 m = 0,186 °C

So t _f solution = t _f water – Δ t _f = 0 °C – 0,186 °C = – 0,186 °C

Its outgrows tetapan molal's boiling point (k _b ) and molal's freezing point (k _f ) severally dissolving is as on following table: 

Dissolving	Freezing point(°C )	k f (°C / m)	Boiling point(°C )	k b (°C / m)
Water	0,0	1,86	100,0	0,512
Acetate	16,6	3,9	117,9	3,07
Benzene	5,50	4,9	80,1	2,53
Kamfor	179,8	39,7	207,42	5,61
Nitrobenzena	5,7	7,0	210,8	5,24
Phenol	40,90	7,4	181,75	3,56