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!Which reactant to use to calculate the amount of heat released or absorbed? (1 Viewer)

fabl

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!Which reactant to use to calculate the amount of heat released or absorbed? Does it matter?

I tried to find the mols of NH4SCN and then multiplied it with the delta H.
but the answer used barium hydroxide instead???

50 g NH4SCN is mixed with slight excess barium hydroxide, and the delta H is +2180 kj/mol. calculate the amount of heat released or absorbed? which one is it?

Thanks
 

InteGrand

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!Which reactant to use to calculate the amount of heat released or absorbed? Does it matter?

I tried to find the mols of NH4SCN and then multiplied it with the delta H.
but the answer used barium hydroxide instead???

50 g NH4SCN is mixed with slight excess barium hydroxide, and the delta H is +2180 kj/mol. calculate the amount of heat released or absorbed? which one is it?

Thanks
Well it sounds like it should be NH4SCN.

Molar mass of ammonium thiocyanate (NH4SCN) is 76.122 g/mol, so the number of molecules of NH4SCN in 50 g of NH4SCN is .

Since , the reaction is endothermic, which means heat is absorbed from the surroundings.

So the heat absorbed should be to 1 sig. fig.

Is this the answer you got?
 
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