Please explain clearly and with steps if possible! Thank you :) Mapa enera Donal
ID: 914678 • Letter: P
Question
Please explain clearly and with steps if possible! Thank you :)
Mapa enera Donald McQuarrie.Peter A Rock Ethan Gallogy University Science Books presented by Sapling Learning Copper(1) ions in aqueous solution react with NH3(aq) according to Cu"(aq) +2NH3(aq) -> Cu(NH3),(aq) K' = 6.3 x 1010 M-2 Calculate the solubility (in g L- of CuBr(s) in 0.14 M NHs(aq). Number g/L nuint- OPrev o s@ove Up SView Sout one eck Answer 0Neat - Exit Hint - The equation for the solubility of Curs)in NHs(aq) CuBr(s) +2NH,(aq) Cu(NH3)2(aq)+Br(aq) is the sum of two equations; (1) the equation that corresponds to the Ksp of CuBr and (2) the equation that corresponds to the K of Cu(NH3)2.Explanation / Answer
Answer – We are given the [NH3] = 0.14 M
Reaction –
CuBr(s) + 2NH3(aq) <----->Cu(NH3)+(aq) + Br-(aq)
We need to first calculate the Ka for this reaction- this is tge combination of reaction of Kf and Ksp.
We know when two equilibrium constant added there gets multiplication
So, Ka= Kf * Ksp
= 6.3*1010 M-2 * 6.3*10-9
= 396.9
Now we need to put ICE chart
CuBr(s) + 2NH3(aq) <----->Cu(NH3)2+(aq) + Br-(aq)
I 0.14 0 0
C -2x +x +x
E 0.14-2x +x +x
So Ka = [Cu(NH3)2+(aq)] [Br-(aq)] / [NH3(aq)]2
396.9 = x *x / ( 0.14-2x)2
396.9 ( 0.14-2x)2 = x2
396.9 (4x2 -0.56x +0.0196) = x2
1587.6x2 -222.3x + 7.779 = x2
1586.6x2 -222.3x + 7.779 = 0
By using the quadratic equation –
x = 0.0679
so, [Cu(NH3)2+(aq)] = [Br-(aq)] = x = 0.0679 M
so, the molar solubility of CuBr(s) = 0.0679 moles /L* 143.45 g/mol
= 9.74 g/L