Answer: The enthalpy of formation of
is -396 kJ/mol
Explanation:
Calculating the enthalpy of formation of 
The chemical equation for the combustion of propane follows:

The equation for the enthalpy change of the above reaction is:
![\Delta H^o_{rxn}=[(2\times \Delta H^o_f_{(SO_3(g))})]-[(2\times \Delta H^o_f_{(SO_2(g))})+(1\times \Delta H^o_f_{(O_2(g))})]](https://tex.z-dn.net/?f=%5CDelta%20H%5Eo_%7Brxn%7D%3D%5B%282%5Ctimes%20%5CDelta%20H%5Eo_f_%7B%28SO_3%28g%29%29%7D%29%5D-%5B%282%5Ctimes%20%5CDelta%20H%5Eo_f_%7B%28SO_2%28g%29%29%7D%29%2B%281%5Ctimes%20%5CDelta%20H%5Eo_f_%7B%28O_2%28g%29%29%7D%29%5D)
We are given:

Putting values in above equation, we get:
![-198=[(2\times \Delta H^o_f_{(SO_3(g))})]-[(2\times \Delta -297)+(1\times (0))]\\\\\Delta H^o_f_{(SO_3(g))}=-396kJ/mol](https://tex.z-dn.net/?f=-198%3D%5B%282%5Ctimes%20%5CDelta%20H%5Eo_f_%7B%28SO_3%28g%29%29%7D%29%5D-%5B%282%5Ctimes%20%5CDelta%20-297%29%2B%281%5Ctimes%20%280%29%29%5D%5C%5C%5C%5C%5CDelta%20H%5Eo_f_%7B%28SO_3%28g%29%29%7D%3D-396kJ%2Fmol)
The enthalpy of formation of
is -396 kJ/mol
Old and inefficient mining smokestacks contaminate the soil around abandoned mine sites.
<h3>What are mines?</h3>
A mine is an area from which natural resources are extracted such as coal, metals, etc. A mine is known to be the source of many heavy metals as well as acid.
As such the statement that does not represent the impact of mining services is that; "Old and inefficient mining smokestacks contaminate the soil around abandoned mine sites".
Learn more about mine sites:brainly.com/question/25875677
#SPJ1
Answer:
[H+] = 4.365x10⁻¹¹
Explanation:
The pH is a measurement widely used in chemistry. Is used in quality control to determine if a product is good for human or pet consumption. The equation to obtain the pH is:
pH = -log [H+]
To solve [H+]:
10^pH = -[H+]
10^-pH = -[H+]
In the problem:
10^-10.36 = -[H+]
<h3>[H+] = 4.365x10⁻¹¹</h3>
One kilogram is the answer
The average atomic mass of Boron: 10.431 amu
<h3>Further explanation
</h3>
Isotopes are atoms whose no-atom has the same number of protons while still having a different number of neutrons.
So Isotopes are elements that have the same Atomic Number (Proton)
Atomic mass is the average atomic mass of all its isotopes
In determining the mass of an atom, as a standard is the mass of 1 carbon-12 atom whose mass is 12 amu
Mass atom X = mass isotope 1 . % + mass isotope 2.% + ...
The average atomic mass of boron :
