<span>Answer is: pH of solution of sodium cyanide is 11.3.
Chemical reaction 1: NaCN(aq) → CN</span>⁻(aq)
+ Na⁺<span>(aq).
Chemical reaction 2: CN</span>⁻ +
H₂O(l) ⇄ HCN(aq) + OH⁻<span>(aq).
c(NaCN) = c(CN</span>⁻<span>)
= 0.021 M.
Ka(HCN) = 4.9·10</span>⁻¹⁰<span>.
Kb(CN</span>⁻) = 10⁻¹⁴ ÷
4.9·10⁻¹⁰ = 2.04·10⁻⁵<span>.
Kb = [HCN] · [OH</span>⁻]
/ [CN⁻<span>].
[HCN] · [OH</span>⁻<span>] =
x.
[CN</span>⁻<span>] = 0.021 M - x..
2.04·10</span>⁻⁵<span> = x² / (0.021 M
- x).
Solve quadratic equation: x = [OH</span>⁻<span>] = 0.00198 M.
pOH = -log(0.00198 M) = 2.70.
pH = 14 - 2.70 = 11.3.</span>
The volume of concentrated HCl : 2.073 ml
<h3>Further explanation</h3>
Given
37% HCl by mass; density 1.19 g/mL
Required
The volume of concentrated HCl
Solution
Conversion to molarity :
37% x 1.19 g/ml =0.4403 g/ml
g/ml to mol/L :
=0.4403 g/ml x 1000 ml/L : 36.5 g/mol
=12.06 mol/L
or we can use formula :

Dilution formula :
M₁V₁=M₂V₂
12.06 M x V₁ = 0.1 M x 0.25 L
V₁ = 0.0021 L = 2.073 ml
Latent heat of fusion for ice is 33600J/k
Heat absorbed
- k_f×m
- 31.6×33600
- 1061,740mJ
- 1061J
Answer:
when 3-phenylpropanoic, PhCH₂CH₂COOH , is treated with NaOH, H₂0 it produce sodium salt of 3 - phenylpropanoic acid with water as a major product.
Explanation:
Carboxylic acid when treated with a base like NaOH or KOH gives carboxylate ion because H⁺ from acid reacts with OH⁻ from base gives H₂0 and salt of sodium carboxylate.
The mechanism of the above reaction given below
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