For ammonia, ▲H fusion is 5.66 kJ/mol, and ▲S fusion is 29.0 J/mol x K. ▲H vaporization is 23.33 kJ/mol and ▲S vaporization is 97.2 J/mol x K.
The answers I got were: 195.2 K and 240 K
Is this right? If not, please explain how to solve this!
The answers I got were: 195.2 K and 240 K
Is this right? If not, please explain how to solve this!
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Assuming you're asked to find the melting point and the boiling point.
Your answers do match the values given at http://en.wikipedia.org/wiki/Ammonia
You should put a decimal point after the 0 in 240. to indicate 3 digit precision.
The concept is ΔG = ΔH - TΔS
Since the melting point and boiling points are equilibrium conditions, ΔG = 0
and therefore ΔH = TΔS
Just solve for T.
The only catch is that ΔH has units of kJ and ΔS units of J, so make sure to make them the same.
T will be in K as you indicated.
Your answers do match the values given at http://en.wikipedia.org/wiki/Ammonia
You should put a decimal point after the 0 in 240. to indicate 3 digit precision.
The concept is ΔG = ΔH - TΔS
Since the melting point and boiling points are equilibrium conditions, ΔG = 0
and therefore ΔH = TΔS
Just solve for T.
The only catch is that ΔH has units of kJ and ΔS units of J, so make sure to make them the same.
T will be in K as you indicated.