Answer:
V = 36.7L of 
Explanation:
1. Write the chemical reaction for the decomposition of sodium azide:
2. Find the number of moles of produced by the decomposition of 71.4g of 
:
3. Use the ideal gas equation to find the Volume of occupied by 1.65 moles of , at the temperature and pressure given by the problem:
Solving for V:
Converting the temperature from ◦C to K:
25◦C+273.15=298.15K
Replacing values:
V=36.7L of
To solve this problem, we should recall that
the change in enthalpy is calculated by subtracting the total enthalpy of the reactants
from the total enthalpy of the products:
ΔH = Total H of products – Total H of reactants
You did not insert the table in this problem, therefore I
will find other sources to find for the enthalpies of each compound.
ΔHf CO2 (g) = -393.5 kJ/mol
ΔHf CO (g) = -110.5 kJ/mol
ΔHf Fe2O3 (s) = -822.1 kJ/mol
ΔHf Fe(s) = 0.0 kJ/mol
Since the given enthalpies are still in kJ/mol, we have to
multiply that with the number of moles in the formula. Therefore solving for ΔH:
ΔH = [<span>3 mol </span><span>( − </span><span>393.5 </span>kJ/mol<span>) + 1 mol (</span>0.0
kJ/mol)<span>] − [</span><span>3 mol </span><span>( − </span><span>110.5 </span>kJ/mol<span>) + </span><span>2 mol </span><span>( − </span><span>822.1 </span>kJ/mol<span>)]</span>
ΔH = <span>795.2
kJ</span>
Answer:
Explanation:
Hello,
In this case, given the acid, we can suppose a simple dissociation as:
Which occurs in aqueous phase, therefore, the law of mass action is written by:
![Ka=\frac{[H^+][A^-]}{[HA]}](https://tex.z-dn.net/?f=Ka%3D%5Cfrac%7B%5BH%5E%2B%5D%5BA%5E-%5D%7D%7B%5BHA%5D%7D)
That in terms of the change 
due to the reaction's extent we can write:
But we prefer to compute the Kb due to its exceptional weakness:
Next, the acid dissociation in the presence of the base we have:
![Kb=\frac{[OH^-][HA]}{[A^-]}=1x10^{6}=\frac{x*x}{0.1-x}](https://tex.z-dn.net/?f=Kb%3D%5Cfrac%7B%5BOH%5E-%5D%5BHA%5D%7D%7B%5BA%5E-%5D%7D%3D1x10%5E%7B6%7D%3D%5Cfrac%7Bx%2Ax%7D%7B0.1-x%7D)
Whose solution is 
which equals the concentration of hydroxyl in the solution, thus we compute the pOH:
![pOH=-log([OH^-])=-log(0.0999)=1](https://tex.z-dn.net/?f=pOH%3D-log%28%5BOH%5E-%5D%29%3D-log%280.0999%29%3D1)
Finally, since the maximum scale is 14, we can compute the pH by knowing the pOH:
Regards.
Exothermic change. Because the firework when it exploded, released energy in the form of light. In exothermic changes energy is released, and in endothermic changes energy is absorbed.
- This wouldn't be a physical change, but instead a chemical change. A clue that it is a chemical change is that energy was given off.
First, let's start off by finding the mass of this whole hydrate.
(Note: the unit of measurement for mass will be amu)
Let's find the molecular mass of each element.
Now, let's find the mass of each compound.
We have 6 molecules of H2O, so multiply 18.015 by 6 then add that with the weight of CoCl2.
Now divide 108.09 (mass of all the H2O in the hydrate) by 237.923 (total mass of hydrate).
Turn that into a percentage and you get 45.431%.
Hope this helps! :)
