Answer:
The correct answer is 5.447 × 10⁻⁵ vacancies per atom.
Explanation:
Based on the given question, the at 750 degree C the number of vacancies or Nv is 2.8 × 10²⁴ m⁻³. The density of the metal is 5.60 g/cm³ or 5.60 × 10⁶ g/m³. The atomic weight of the metal given is 65.6 gram per mole. In order to determine the fraction of vacancies, the formula to be used is,
Fv = Nv/N------ (i)
Here Nv is the number of vacancies and N is the number of atomic sites per unit volume. To find N, the formula to be used is,
N = NA×P/A, here NA is the Avogadro's number, which is equivalent to 6.022 × 10²³ atoms per mol, P is the density and A is the atomic weight. Now putting the values we get,
N = 6.022 × 10²³ atoms/mol × 5.60 × 10⁶ g/m³ / 65.6 g/mol
N = 5.14073 × 10²⁸ atoms/m³
Now putting the values of Nv and N in the equation (i) we get,
Fv = 2.8 × 10²⁴ m⁻³ / 5.14073 × 10²⁸ atoms/m^3
Fv = 5.44669 × 10⁻⁵ vacancies per atom or 5.447 × 10⁻⁵ vacancies/atom.
Answer: pH of an 
solution is 4.34
Explanation:
pH or pOH is the measure of acidity or alkalinity of a solution.
pH is calculated by taking negative logarithm of hydrogen ion concentration.
![pH=-\log [H^+]](https://tex.z-dn.net/?f=pH%3D-%5Clog%20%5BH%5E%2B%5D)
Putting in the values:
![pH=-\log[4.58\times 10^{-5}]](https://tex.z-dn.net/?f=pH%3D-%5Clog%5B4.58%5Ctimes%2010%5E%7B-5%7D%5D)
Thus pH of an solution if the ![[H^+]](https://tex.z-dn.net/?f=%5BH%5E%2B%5D)
is ![4.58\times 10^{-5}]](https://tex.z-dn.net/?f=4.58%5Ctimes%2010%5E%7B-5%7D%5D)
is 4.34
The highest atom economy
2CO + O₂ ⇒ 2CO₂
<h3>Further explanation</h3>
Given
The reaction for the production of CO₂
Required
The highest atom economy
Solution
In reactions, there are sometimes unwanted products that can be said to be a by-product or a waste product. Meanwhile, the desired product can be said to be a useful product, which can be shown as the atom economy
of the reaction
the higher the atomic economy value of a reaction, the smaller the waste/ byproducts produced, so that less energy is wasted
The general formula:
Atom economy = (mass of useful product : mass of all reactants/products) x 100
<em>or
</em>
Atom economy = (total formula masses of useful product : total formula masses of all reactants/products) x 100
So a reaction that only produces one product will have the highest atomic value, namely the reaction in option C
Answer:
Endergonic reaction or nonspontaneous reaction.
Explanation:
Gibbs free energy is a state function that determines the spontaneity or feasibility of the given reversible chemical reaction, at fixed pressure and temperature. It is given by the equation:
ΔG = ΔH - TΔS
Here, ΔG - change in Gibbs free energy
ΔH- The change in enthalpy of reaction
ΔS - The change in entropy
T- Temperature
When the <u>change in the Gibbs free energy for a given reaction is positive</u> (ΔG > 0), then that chemical reaction is known as an endergonic reaction or nonspontaneous reaction.
