Answer:
- 0.0249% Sb/cm
Explanation:
Given that:
One surface contains 1 Sb atom per 10⁸ Si atoms and the other surface contains 500 Sb atoms per 10⁸ Si atoms.
The concentration gradient in atomic percent (%) Sb per cm can be calculated as follows:
The difference in concentration = 
The distance 
= 0.2-mm = 0.02 cm
Now, the concentration of silicon at one surface containing 1 Sb atom per 10⁸ silicon atoms and at the outer surface that has 500 Sb atom per 10⁸ silicon atoms can be calculated as follows:
= - 0.0249% Sb/cm
b) The concentration 
of Sb in atom/cm³ for the surface of 1 Sb atoms can be calculated by using the formula:
Lattice parameter = 5.4307 Å; To cm ; we have
= 
= 
The concentration 
of Sb in atom/cm³ for the surface of 500 Sb can be calculated as follows:
= 
= 
Finally, to calculate the concentration gradient
Answer:
A scientific question to be asked is; <em>What is the average speed of the toy car?</em>
Explanation:
A scientific question is a question which is well defined, the values in the question can be measured, and the inputs and outputs related to the question are controllable
The parameters measured in the experiment are;
The time elapsed during the movement of the car, <em>Δt</em>
The distance the car moves, <em>d</em>
From the obtained measurements, the value can be calculated is the average speed of the toy car as follows;
Therefore, a scientific question to be asked that will be answered by doing the experiment is; What is the average speed of the toy car?
Answer:
A) homotopic and B) enantiotopic
Explanation:
Protons chemically equivalent are those that have the same chemical shift, also if they are interchangeable by some symmetry operation or by a rapid chemical process.
The existence of symmetry axes, Cn, that relate to the protons results in the protons being homotopic, that is chemically equivalent in both chiral and aquiral environments.
The existence of a plane of symmetry, σ, makes the protons related by it, are enantiotopic and these protons will only be equivalent in an aquiral medium; if the medium is chiral both protons will be chemically NOT equivalent. The existence of a center of symmetry, i, in the molecule makes the related protons through it enantiotopic and therefore chemically only in the aquiral medium.
Diastereotopic protons cannot be interconverted by any symmetry operation and they are different, with different chemical displacement.
Actually the strength
of London dispersion forces highly depend on the total number of electrons and
the area in which they are spread. We can see clearly that iodine will have the
strongest LDF's, and hence, have the highest boiling point (and melting point).
This is also the reason why iodine is a solid at room temperature, bromine is liquid
and chlorine and fluorine are gases.
Answer:
<span>Fluorine (F2)</span>
<span>We know that density is equal to mass divided by volum, D=M/V and in this case we have 1 gallon of a solution of sulfuric acid with 37.4% of concentration in mass.
1 gallon is 3785.41 ml and according the formula M=D*V = 1.31 * 3785.41 = 4958.89 grams of solution.
Only 37.4% of the solution is sulfuric acid, that is 4958.89 * 37.4/100= 1854.62 grams
Then the number of grams of sulfuric acid is 1854.62 gr.</span>
