Answer: The standard enthalpy of formation of 
is -252.1 kJ/mol.
Explanation:
The balanced chemical reaction is,
The expression for enthalpy change is,
![\Delta H=[n\times H_f_{products}]-[n\times H_f_{reactantss}]](https://tex.z-dn.net/?f=%5CDelta%20H%3D%5Bn%5Ctimes%20H_f_%7Bproducts%7D%5D-%5Bn%5Ctimes%20H_f_%7Breactantss%7D%5D)
Putting the values we get :
![\Delta H=[2\times H_f{Fe}+3\times H_f{H_2O}]-[1\times H_f{Fe_2O_3}+3\times H_f{H_2}]](https://tex.z-dn.net/?f=%5CDelta%20H%3D%5B2%5Ctimes%20H_f%7BFe%7D%2B3%5Ctimes%20H_f%7BH_2O%7D%5D-%5B1%5Ctimes%20H_f%7BFe_2O_3%7D%2B3%5Ctimes%20H_f%7BH_2%7D%5D)
![67.9kJ=[(2\times 0)+(3\times H_f{H_2O})]-[(1\times -824.2kJ/mol)+3\times 0kJ/mol)]](https://tex.z-dn.net/?f=67.9kJ%3D%5B%282%5Ctimes%200%29%2B%283%5Ctimes%20H_f%7BH_2O%7D%29%5D-%5B%281%5Ctimes%20-824.2kJ%2Fmol%29%2B3%5Ctimes%200kJ%2Fmol%29%5D)
Thus standard enthalpy of formation of is -252.1 kJ/mol.
So I believe you are supposed to take notes based on the guiding questions (the questions on the side).
Explanation:
Crystallography. an arrangement in space of isolated points (lattice points ) in a regular pattern, showing the positions of atoms, molecules, or ions in the structure of a crystal.
If an atom experiences sufficient thermal activation, it can move to a neighboring lattice position.4 If the vibration frequency of the atom is v and the atom has Z nearest neighbors, the total number of jump attempts is vZ. However, only a small fraction of the attempts will be successful, with a probability depending on the ratio between the necessary activation energy for a single jump QD and the thermal activation kBT. The effective jump frequency ΓD is then
(5.6)
With each successful jump, the atom travels one atomic distance λ and the total traveling distance in unit time is thus ΓDλ. Substituting the jump frequency ΓD into the expression for the root mean square displacement of a random walker [equation (5.5)] and using the spatial coordinate r leads to
Try to untie the knot from the balloon let some air out and tie if back....
Answer:
The answer to your question is: the first option
Explanation:
Meter is a unit of length in the SI, international system of units. Its symbol is m.
Nanometer is equivalent to 10⁻⁹ meters, as its name says it is used to measure extremely small particles.
-To solve this problem we use a rule of three.
1 meter ⇒ 10⁹ nanometers
x meters ⇒ 670 nanometers
Simplify
x = (670 x 1)/( 10⁹)
x = 6.7 x 10 ⁻⁷ meters
