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A level chemistry help.... I need urgent help

The standard enthalpy change of solution for ammonium nitrate, NH4NO3 , is +25.7 kJ mol–1.

(a) Calculate the value for the standard entropy change in the surroundings, ∆Ssurroundings , when ammonium nitrate dissolves in water at 298 K.
Include a sign and units with your answer. [2 marks]

(b) Explain what can be deduced from your answer in (a) about the sign and the value of the standard entropy change in the system, ∆Ssystem , when NH4NO3 dissolves. [3 marks]

Can someone please help me with this question? Thanks in advance

For (a) I got -86.24 J mol^-1 K^-1 but I’m not sure
I got the same for part (a)

For (b), I’m not completely sure, but I’d assume the entropy of system has to be positive, and by a larger amount than the entropy of surroundings (so over 86.2) in order for the total entropy to be positive and therefore feasible. Ill show the question to my chem tutor later on and get back to you on what they say :smile:
Reply 2
Original post by medicnia20
I got the same for part (a)

For (b), I’m not completely sure, but I’d assume the entropy of system has to be positive, and by a larger amount than the entropy of surroundings (so over 86.2) in order for the total entropy to be positive and therefore feasible. Ill show the question to my chem tutor later on and get back to you on what they say :smile:


Thank you so much.
would you please help me with some other questions? I don’t wanna be a burden so it’s totally fine if you refuse
Original post by S.78_t
Thank you so much.
would you please help me with some other questions? I don’t wanna be a burden so it’s totally fine if you refuse

Sure, i think I’m doing the same set of questions as you, so we can help each other out :smile:
Reply 4
Original post by medicnia20
Sure, i think I’m doing the same set of questions as you, so we can help each other out :smile:


Great... would you like to help each other out on social media rather than here?
(edited 2 years ago)
Original post by S.78_t
Great... would you like to help each other out on social media rather than here?

My ig id is s.78_t

i don’t have an instagram, give me a second and i’ll make one quick
Reply 6
Original post by medicnia20
i don’t have an instagram, give me a second and i’ll make one quick


Sure.. I accepted your follow request.. please accept mine
Original post by S.78_t
The standard enthalpy change of solution for ammonium nitrate, NH4NO3 , is +25.7 kJ mol–1.

(a) Calculate the value for the standard entropy change in the surroundings, ∆Ssurroundings , when ammonium nitrate dissolves in water at 298 K.
Include a sign and units with your answer. [2 marks]

(b) Explain what can be deduced from your answer in (a) about the sign and the value of the standard entropy change in the system, ∆Ssystem , when NH4NO3 dissolves. [3 marks]

Can someone please help me with this question? Thanks in advance

For (a) I got -86.24 J mol^-1 K^-1 but I’m not sure


what exam board is this for?
Original post by eliana100
Edexcel do you have the ms for this paper

what year is it from?
(edited 2 years ago)

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