Is a hydrate affected by a coeffiecient?

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The discussion centers on balancing the chemical reaction involving barium hydroxide hydrate and ammonium thiocyanate. Participants emphasize that the coefficients in front of the reactants affect the number of water molecules in the hydrate, maintaining a consistent ratio. Specifically, the ratio of barium to water in the hydrate is always 1:8, meaning any coefficient applied to barium must also adjust the water count accordingly. The incorrect attempts at balancing highlight the importance of recognizing bound versus unbound water in the products. Understanding these relationships is crucial for achieving the correct balanced equation.
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Homework Statement



Ba(OH)2 · 8 H2O(s) + NH4SCN(s) → Ba(SCN)2(s) + H2O(l) + NH3(g)

Homework Equations



i have to balance this reaction

The Attempt at a Solution



2Ba(OH)2 * 8H2O(s) + 4NH4SCN(s) --> 2Ba(SCN)2(s) +12H2O(l) + 4NH3(g)this isn't the right answer because the webassign keeps marking it wrong. i think it boils down to whether a coefficient affects a hydrate or not but idk. thanks in advance for any tips u can provide :)
 
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Notice that all the coefficients in your answer are divisible by 2.
 
reducing it to 0:2:6:2 isn't the answer
 
Last edited:
Of course it's not. 2 divided by 2 does not equal 0.
 
Your given set of reactants and products shows bound water on the left side, but unbounded water on the products side. This will help you know how many of the waters to tell on the right side (products).

You seem to recognize that the Ba+2 needs two SCN-, so what should this mean for the count of NH4(SCN) on the left side?
 
DDT: i meant 0 as in no coefficient. 1:2:6:2 is not the answer, regardless of my imprecise notation

Thanks for the help, Symbollipoint.
 
torquemada said:

Homework Statement



Ba(OH)2 · 8 H2O(s) + NH4SCN(s) → Ba(SCN)2(s) + H2O(l) + NH3(g)


remember that Ba(OH)2 · 8 H2O(s) is Ba+2 + 2OH- + 8H2O

and 2 [Ba(OH)2 · 8 H2O(s)] is 2Ba+2 + 4OH- + 16H2O

There is always a 1:8 ratio of Ba to H2O in this hydrate. You don't separate them. You put a coefficient in front of the Barium and it affects the number of water molecules as well.
 
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