Respuesta :
Answer: a) [tex]Pb^{2+}(aq)+2Cl^-(aq)\rightarrow PbCl_2(s)[/tex]: negative
b) [tex]CaCO_3(s)\rightarrow CaO(s)+CO_2(g)[/tex] : positive
c) [tex]2NH_3(g)\rightarrow N_2(g)+3H_2(g)[/tex]: positive.
d) [tex]P_4(g)+5O_2(g)\rightarrow P_4O_{10}(s)[/tex] : negative
e) [tex]C_4H_8(g)+6O_2(g)\rightarrow 4CO_2(g)+4H_2O(g)[/tex]: positive.
f) [tex]I_2(s)\rightarrow I_2(g)[/tex] : positive.
Explanation:
Entropy is the measure of randomness or disorder of a system. If a system moves from an ordered arrangement to a disordered arrangement, the entropy is said to decrease and vice versa.
[tex]\Delta S[/tex] is positive when randomness increases and [tex]\Delta S[/tex] is negative when randomness decreases.
a) [tex]Pb^{2+}(aq)+2Cl^-(aq)\rightarrow PbCl_2(s)[/tex]
As ions are moving to solid form , randomness decreases and thus sign of [tex]\Delta S[/tex] is negative.
b) [tex]CaCO_3(s)\rightarrow CaO(s)+CO_2(g)[/tex]
As solid is changing to gas, randomness increases and thus sign of [tex]\Delta S[/tex] is positive.
c) [tex]2NH_3(g)\rightarrow N_2(g)+3H_2(g)[/tex]
As 2 moles of reactants are converted to 4 moles of products , randomness increases and thus sign of [tex]\Delta S[/tex] is positive.
d) [tex]P_4(g)+5O_2(g)\rightarrow P_4O_{10}(s)[/tex]
As gas is changing to solid, randomness decreases and thus sign of [tex]\Delta S[/tex] is negative.
e) [tex]C_4H_8(g)+6O_2(g)\rightarrow 4CO_2(g)+4H_2O(g)[/tex]
As 7 moles of reactants are converted to 8 moles of products , randomness increases and thus sign of [tex]\Delta S[/tex] is positive.
f) [tex]I_2(s)\rightarrow I_2(g)[/tex]
As solid is changing to gas, randomness increases and thus sign of [tex]\Delta S[/tex] is positive.
