The solubility product of a substance us calculated by the product of the concentration of the dissociated ions in the solution raise to the stoichiometric coefficient of the ions. Therefore, we need the dissociation reaction. For this, it will have the reaction:
PbI2 = Pb^2+ + 2I-
We solve as follows:
Ksp = [Pb2+][I-]^2 = <span>1.4 x 10-8
</span><span>1.4 x 10-8 = x(2x)^2
</span><span>1.4 x 10-8 = 4x^3
x = 1.5x10^-3 M
The molar solubility would be </span>1.5x10^-3 M.
Answer:
Explanation:
a) In an exothermic reaction, the energy transferred to the surroundings from forming new bonds is ___more____ than the energy needed to break existing bonds.
b) In an endothermic reaction, the energy transferred to the surroundings from forming new bonds is ___less____ than the energy needed to break existing bonds.
c) The energy change of an exothermic reaction has a _____negative_______ sign.
d) The energy change of an endothermic reaction has a ____positive________ sign.
The energy changes occur during the bonds formation and bonds breaking.
There are two types of reaction endothermic and exothermic reaction.
Endothermic reactions:
The type of reactions in which energy is absorbed are called endothermic reactions.
In this type of reaction energy needed to break the bond are higher than the energy released during bond formation.
For example:
C + H₂O → CO + H₂
ΔH = +131 kj/mol
it can be written as,
C + H₂O + 131 kj/mol → CO + H₂
Exothermic reaction:
The type of reactions in which energy is released are called exothermic reactions.
In this type of reaction energy needed to break the bonds are less than the energy released during the bond formation.
For example:
Chemical equation:
C + O₂ → CO₂
ΔH = -393 Kj/mol
it can be written as,
C + O₂ → CO₂ + 393 Kj/mol
Answer:
c The concentration(s) of reactant(s) is constant over time.
Step-by-step explanation:
When the reaction A ⇌ B reaches equilibrium, the concentrations of reactants and products are constant over time.
a is <em>wrong</em>, because the concentrations of reactants and products are usually quite different.
b is <em>wrong</em>, because both product and reactant molecules are being formed at equilibrium.
d is <em>wrong</em>. The rates of the forward and reverse reactions are equal, but they are not zero.
Answer:
They become ductile and deform plastically
Explanation:
When rocks are buried by the materials up to a greater depth, then the confining pressure increases significantly. This results in the ductile behavior of the rocks at such depth. These rocks are present in the ductile region where the depth is about more than 20 to 30 km. Here the rocks are subjected to extremely high pressure and temperature conditions, which favors the transformation of rocks into more higher-grade metamorphic rocks. It is also enhanced due to the geothermal gradient.
Under such high pressure and temperature, the rocks show the behavior of plasticity, where the rocks undergo bending, buckling as well as they tend to flow, and there occurs low strain rate, resulting in the permanent deformation of rocks.
Thus, the rocks become ductile and deform plastically at such conditions.
Answer : The volume of stock solution needed are, 12.5 mL
Explanation :
Formula used :
where,
are the initial molarity and volume of copper (II) chloride.
are the final molarity and volume of stock solution of copper (II) chloride.
We are given:
Putting values in above equation, we get:
Hence, the volume of stock solution needed are, 12.5 mL