Dissociation reaction of calcium hydroxide can be represented as follows:
<span>Ca(OH)2 (s) ⇄ Ca2+(aq) + 2OH-(aq)
</span>
The solubility product of Ca(OH)2 is mathematically expressed as
Ksp = [Ca2+] [OH-]^2
Given: Ksp = <span>4.68 x 10-6
Now, we know that for aqueous system, pH + pOH = 14
and pOH = -log(OH-)
Thus, [OH-] = </span><span>10^(pH - 14)
</span>∴ Ksp = [Ca2+] [10^(pH - 14)]^2 = [Ca2+] [10^(2.pH - 28)]
∴ [Ca2+] = Ksp/10^(2.pH - 28)
= Ksp 10^(28 - 2.pH)
Now, at pH = 4
[Ca2+] = Ksp 10^(28 - 2.pH)
= (4.68 x 10-6) 10^(28 - 2X4)
= 4.68 X 10^14 mol/dm3
At pH = 7,
[Ca2+] = Ksp 10^(28 - 2.pH)
= (4.68 x 10-6) 10^(28 - 2X7)
= 4.68 X 10^8 mol/dm3
At pH = 9
[Ca2+] = Ksp 10^(28 - 2.pH)
= (4.68 x 10-6) 10^(28 - 2X9)
= 4.68 X 10^4 mol/dm3
Answer:
Following is molar solubility of calcium hydroxide at different pH
at pH 4 = 4.68 X 10^14 mol/dm3
at pH 7 = 4.68 X 10^8 mol/dm3
at pH 9 = 4.68 X 10^4 mol/dm3
Generally we have to kinds of conductors
a) metallic conductors: which conduct electricity due to free movement of electrons
b) electrolytic conductors: which conduct electricity due to movement of ions.
HCN is an electrolyte and is non conducting in pure state as it has no free ions or electrons
When HCN is dissolved in water it dissociates as

These ions obtained due to dissociation of HCN makes it conducting in nature.
Explanation:
Nuclear power plants deliver electricity 24 hours a day, 7 days a week, irrespective of weather and seasons. As well as reducing greenhouse gas emissions, nuclear generation helps reduce air pollution
Answer:
Neutrons,Electrons and Protons I think.
Mass of Mercury(Hg) : 55.8 g
<h3>Further explanation</h3>
Given
Reaction
2HgO ⇒ O₂ + 2Hg
Required
Mass of Mercury
Solution
Conservation of mass applies to a closed system, where the masses before and after the reaction are the same
So mass of reactants = mass of products
Mass of reactants = mass HgO = 60 g
Mass of products = mass O₂ + mass Hg
60 g = 4.2 g + mass Hg
mass Hg = 60 - 4.2
mass Hg = 55.8 g