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I need help to approach these problems
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In this question, osmotic pressure and pH is given.
This information is used in two ways
First using osmotic pressure (in atm) and R value and temperature (K) we will calculate molarity(M) of weak base (B)
pi(osmotic pressure) = MRT
so M = pi /RT
Now this can be taken as initial concentration of weak base.
pH of solution can be used to calculate pOH
pH +pOH = 14
pOH = 14-pH
Use this information to get [OH-]
[OH-] = 10-pOH
Now we can make equilibrium system of this weak B
RICE table
R B + H2O <-----> BH+ + OH-
I M Calculated above) 0 0
C - X +X +X
E M-X X X
Kb = [BH+] . [OH-]/
Kb = X2/ (M-X)
You know X = [OH-] and you now M so you can calculate Kb
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In this question, you want to calculate amount of Cl2 in 1L of water.You can calculate molarity(M) of solution by using Ka value and RICE table.
pH = 1.19
[H+] = 10 -1.19
RICE table
R Cl2(aq) + H2O (l)<-----> H+(aq) + Cl- (aq) + HOCl(aq)
I M Calculated above) 0 0 0 0
C - X +X +X +X +X
E M-X X X X X
Ka = X3/ (M-X)
You know X = [H+] and you now Ka so you can calculate M
Convert M into moles and moles into grams.
You know M = moles/Volume in L
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pH of solution can be used to calculate pOH
pH +pOH = 14
pOH = 14-pH
Use this information to get [OH-]
[OH-] = 10-pOH
Now we can make equilibrium system of this weakNH3
RICE table
R NH3 + H2O <-----> NH4+ + OH-
I M Calculated above) 0 0
C - X +X +X
E M-X X X
Kb = 1.8 * 10^-5
Kb = X2/ (M-X)
You know X = [OH-] and you now calculate M
From molarity calculate moles of NH3 in 4L
Use ideal gas law
V = nRT/P to calculate volume of NH3 bubbled in 4L of water.