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Given:C=0.45M We know that the dissociation constant (Ka) of HCN=6.28 X10-10 Solution: KCN is salt of strong acid and weak base. Kh=Kw/Ka Kh=1 X 10-14/6.2 * 10-10 Kh =1.613 X10-5 ---- Kh=h2C h2=Kh/C =1.613 X 10-5/0.45 =0.3584 X10-4 ---- h=\/0.3584 X 10-4 h =0.6 X 10-2 ---- For a salt of weak acid and strong base, [OH-] = h X C =0.6 * 10-2 X 0.45 [OH-] =2.7 X 10-3 ---- pOH = -log[OH-] =-[log (2.7 X 10-3)] =-[-3 log 10 + log 2.7] =-[-3 + 0.4314] =3 - 0.4314 pOH = 2.5686 ---- pH + pOH = 14 pH = 14 - pOH =14 - 2.5686 pH = 11.4314 ---- Therefore the pH of 0.45M KCN is = 11.4314.
Wiki User
∙ 14y ago
Wiki User
∙ 6y agoHydrolysis of KCN yields HCN + KOH so the solution will have a pH >7.KCN + H2O ==> KOH + HCN
CN^- + H2O ==> HCN + OH-
Kb = 1x10^-14/6.2x10^-10 = 1.61x10^-5
1.61x10^-5 = [HCN][OH-]/[KCN] = (x)(x)/0.0765
x^2 = 1.2x10^-6
x = 1.1x10^-3 = [OH-]
pOH = 2.96
pH = 14 - 2.96
pH = 11
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What is the pH of KCN?
KCN is a salt of strong base weak acid. Therefore its water solution will be basic. Hence, its pH will be greater than 7. ^So what is its pH?
What is the pH of a solution with 0001 M H3O?
3. since the [H+]=0.001 M then pH= -log[H+] -log(0.001)=3 pH=3.
CuSO4 reacts with KCN to give what?
CuSO4 + KCN --->Cu(CN)2 + K2SO4
What is the pH of 0.1 M HBr?
-log(0.1 M) = 1 pH
What is the pH of 0.001 M NH4Cl?
- log(0.001 M NH4Cl) = 3 pH =====
Does 0.1 M KCN have a pH greater than 7.0?
Yes. Since KCN is a salt of strong base and weak acid,its water solution will be basic.Therefore,0.1M KCN have pH greater than 7,its pH is 11.
What is the pH of KCN?
KCN is a salt of strong base weak acid. Therefore its water solution will be basic. Hence, its pH will be greater than 7. ^So what is its pH?
What is the pH value of calcium cyanide?
Potassium iodide is neutral. So any solution of potassium iodide would have a pH of 7. One note: no substance has a particular pH as pH depends on both the acidity/basicity of a substance and how concentrated it is.
What number of mole is KCN?
The answer will depend on the quantity of KCN.
What is the pH of a solution with 0001 M H3O?
3. since the [H+]=0.001 M then pH= -log[H+] -log(0.001)=3 pH=3.
What would cause addition of KCN to water?
Since potassium cyanide (KCN) is highly poisonous, the addition of KCN to water might be caused by an intention to kill.
What is the pH of 0.1 M HBr?
-log(0.1 M) = 1 pH
How fast KCN kills human?
KCN kills a human being in 0.5 second.
CuSO4 reacts with KCN to give what?
CuSO4 + KCN --->Cu(CN)2 + K2SO4
What is the formula for the compound that forms from potassium and cyanide?
To answer this you need a roman numeral on gold to know the charge on it. Assuming it would be (I)... the formula would be KAu(CN)2
What is the pH of 0.001 M NH4Cl?
- log(0.001 M NH4Cl) = 3 pH =====
A volume of 37 ml of 0.36 m kcn neutralizes a 75 ml sample of hclo solution what is the concentration of hclo?
M1 and v1 --> KCN M2 and v2 --> HClO ------SO, M1 * v1=M2 * v2 0.36 * 0.037L=M2 * 0.075L 0.013=M2 * 0.075 M2=0.013/0.075 M2=0.17 M
