Question

2. Concentration measures

We have a 0.16% aqueous solution by mass of KOH that has a density of 1.04 g / mL. The molarity of the solution in moles / L.

a. The molarity of this solution is_____.
b. The molality of this solution is approximately_______.
c. The concentration in parts per thousand is______.
d. . The concentration in parts per million is______.
e. The concentration in parts per billion is______.
f. Explain, why can't we determine the exact molal concentration? Can we only determine it approximately?
g. Explain, why in this case can we determine an estimated value of the molal concentration?

Answer 1

Ant to mass = mass N100 totec MOPS S7070 MTOTOD 3 9416+1 :016 mood x700 volume criven thout deorside - 1.04 o me derwity's nicege - l0u = 0.0896 vol. vol. = 0.0896 7:04 in devues 0.086 Metre e molarity moles Of *OU X1000 volline in meine P S briven mase mico * 1000 Volume my M = 0.0496/57 x100o = TM=18.60 moel ] 0.086 al moealitys (m)= moles of koy 0.16 = mass alto Pi m ages of solument (k9). Ma 0.009677 wrot me 0.0096157 mi l magos = 0.02889 Diss . Dio 2889 m = 55,55 mol/g7 78 00 1 ppm = mase Salute (3) X106 O volume soleme E D.0896 *106 0,086 pem a louxloo pem? Concentraron in ppts 0.0896 x 1011 DI0B6 TalouxOS PRE @ i'm PPB (c) = 0.0896 X100 0.086 Tec) =1104x109 pPo? Il

:eneub's Sjaypeel 2 molauity, celiacalled molle concentration a l on oth the cone of a solate in a solution in terms of amount of substance in a specified amotunt. of mass oth the solventii si in the case of solutions with more thom one plevent, molality can be defined for the mixed solvent considered as a . Pleadowsoeventio_ Que to reason of this, wer can't determine the exact molal concentration, we com only determine apboremotely Valle OS cone, A solution of concentration 1 mol/kg is also em Sometimes denoted as I moral. g) in this case oney given mass percentage of koly. and did not given en of exact value of mass of soerenta Hence we didn't get exact roue of molality! Cmoeal comen). Hence we get oney apne estimated so dato value of moral concentration.