Answer:
Mg^2+ and OH- are the chemical species present at the equilibrium. Mg(OH)2 will not affect the equilibrium.
Explanation:
Step 1: data given
Reactants are Solid Mg(OH)2 and H2O(l)
Kc1 = 1.8 * 10^-11
Step 2: The balanced equation
Mg(OH)2(s) ⇄ Mg2+(aq) + 2OH-(aq)
Step 3: Define the equilibrium constant Kc
Kc = [OH-]²[Mg^2+]
Pure solids and liquids do not have any effect or influence on the equilibrium in the reaction. So they are not included in the equilibrium constant expression.
This means Mg^2+ and OH- are the chemical species present at the equilibrium. Mg(OH)2 will not affect the equilibrium.
Answer:
Hg(NO3)2 + Na2CO3 --> 2NaNO3 + HgCO3
We will take that molar mass of Pb(CO3)2 represents the total mass of all particles in this compound, ie it has value 100%.
M(Pb(CO3)2) = Ar(Pb) + 2xAr(C) + 6xAr(O) = 207.2 + 2x12 + 6x16= 327.2 g/mol
M(Pb) = 207.2 g/mol
From the date above we can set the following ratio:
M(Pb(CO3)2) : M(Pb) = 100% : x
327.2 : 207.2 = 100 :x
x = 63.33% of Pb there is in <span>Pb(Co3)2</span>
<span>c.
reactivity
this is a physical property depends on how reactive something is</span>
<span>The best choice is hypochlorous acid nitrous acid (HNO2) because it has the nearest value of pK to the desired pH.
pKa of </span>nitrous acid<span> is 3.34
If we know pKa and pH values, we can calculate the required ratio of conjugate base (NO2⁻) to acid (HNO2) from the following equation:
pH=pKa + log(conc. of base)/( conc. of acid)
</span><span>3.19=3.34 + log c(NO2⁻)/c(HNO2)
</span><span>3.19 - 3.34 = log c(NO2⁻)/c(HNO2)
-0.15 = log c(NO2⁻)/c(HNO2)
c(NO2⁻)/c(HNO2) = 10⁰¹⁵ = 1.41
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