Chapter 9 Solutions
Chapter 9 Solutions
Physical Chemistry Solutions Solution Composition A solution is a homogeneous mixture: that is a solution is a one-phase system with more than one component e The mole fraction x; of species i is defined by x (1.6 ot The(molar) concentration (or volume concentration)c of species i is defined by (9.1) The mass concentration p, of species i in a solution of → volume v is defined by (92)
Solution Composition Solutions V n c i i (9.1)* A solution is a homogeneous mixture; that is, a solution is a one-phase system with more than one component. The mole fraction xi of species i is defined by tot i i n n x (1.6) The (molar) concentration (or volume concentration) ci of species i is defined by The mass concentration i of species i in a solution of volume V is defined by V mi i (9.2)* Physical Chemistry
Physical Chemistry Solutions Solution Composition The molarity is the molar concentration of a species for liquid solutions in moles per liter(dm Solvent(A) Solution Solute(B The molarity m, of species i in a solution is defined by The solute molarity mB IS M4=nAM4(1.4) B B B (9,3) aA
Solution Composition Solutions A i i w n m The molarity is the molar concentration of a species for liquid solutions in moles per liter (dm3 ). The molarity mi of species i in a solution is defined by The solute molarity mB is A A B A B B n M n w n m = (9.3)* Solution Solvent (A) Solute (B) wA = nA MA (1.4) Physical Chemistry
Physical Chemistry Solutions Partial Molar Quantities Partial molar volumes mn+nym2+…+nm=∑nm (9.4) V(H,O)/cm cm 7550250 The star indicates a property 1001 of a pure substance or a collection of pure substances 99 Addition of 50.0 cm of water to 98 50.0 cm of ethanol at 20 oC and 97 I atm gives a solution of 96.5 cm(Fig. 9.1, left) 96 0255075100 (ethanol)cm ≠卩
Partial Molar Quantities Solutions The star indicates a property of a pure substance or a collection of pure substances. = + + + = i V nVm n Vm nr Vm r ni Vm i * , * , * 2 ,2 * 1 ,1 * (9.4) Partial Molar Volumes 0 25 50 75 100 V (ethanol)/cm3 100 99 98 97 96 75 50 25 0 V (H2O)/cm3 V /cm3 Addition of 50.0 cm3 of water to 50.0 cm3 of ethanol at 20 oC and 1 atm gives a solution of 96.5 cm3 (Fig. 9.1, left). * V V Physical Chemistry
Physical Chemistry Solutions s Partial Molar Quantities (1)different intermolecular forces ≠ (2)different packing of molecules V/cm V(H,O)/cm (different sizes and shapes of the 7550250 100 molecules being mixed 99 V=V(T,P,n12…,n) U=U(7,P,n1 (9.5) 98 The total differential of v 97 o dt+ T aP P. T 96 (9.6) 0255075100 o o dn,+…+ V(ethanol)/cm r/T P, nier
Partial Molar Quantities Solutions 0 25 50 75 100 V (ethanol)/cm3 100 99 98 97 96 75 50 25 0 V (H2O)/cm3 V /cm3 * V V (1) different intermolecular forces (2) different packing of molecules (different sizes and shapes of the molecules being mixed) ( , , , , ) ( , , , , ), 1 1 r r U U T P n n V V T P n n = = (9.5) The total differential of V r T P n r T P n P n T n dn n V dn n V dP P V dT T V dV i i r i i + + + + = , , 1 1 , , , , 1 (9.6) Physical Chemistry