The balanced reaction is:
<span>4Cr(s)+3O2 (g )= Cr2O3 (s)
Since we are not given the amount of any of the reactants, we assume we have one gram of chromium. Calculations are as follows:
1 g Cr ( 1 mol Cr / 52 g Cr ) ( 1 mol Cr2O3 / 4 mol Cr ) = <span>0.005 mol Cr2O3
</span></span>0.005 mol Cr2O3 (151.99 g Cr2O3 / 1 mol Cr2O3 ) = 0.7307 g <span>Cr2O3
</span>
Therefore, the theoretical yield for 1 gram of Cr is 0.005 mol Cr2O3 or 0.7307 g Cr2O3.
These would be your answers!
(taken from a source)
Follow the scientific method
Keep detailed records
Communicate experimental results
Hope that helped!
:)
Answer:
C 16
Explanation:
Since there are 6 valence electrons, this belongs in the same column as Oxygen. In fact, this is a diagram of a neutral oxygen atom with 8 total electrons.
Answer: The pH at equivalence point for the given solution is 5.59.
Explanation:
At the equivalence point,
So, first we will calculate the moles of 
as follows.
= 0.0845 mol
Now, volume of 
present will be calculated as follows.
Volume = 
= 
= 0.1891 L
Therefore, the total volume will be the sum of the given volumes as follows.
110 ml + 189.1 ml
= 299.13 ml
or, = 0.2991 L
Now, ![[CH_{3}NH_{3}^{+}] = \frac{0.0845 mol}{0.2991 L}](https://tex.z-dn.net/?f=%5BCH_%7B3%7DNH_%7B3%7D%5E%7B%2B%7D%5D%20%3D%20%5Cfrac%7B0.0845%20mol%7D%7B0.2991%20L%7D)
= 0.283 M
Chemical equation for this reaction is as follows.
As, 
= 
= 
Now, ![[HNO_{3}] = \sqrt{k_{a}[CH_{3}NH_{3}^{+}]}](https://tex.z-dn.net/?f=%5BHNO_%7B3%7D%5D%20%3D%20%5Csqrt%7Bk_%7Ba%7D%5BCH_%7B3%7DNH_%7B3%7D%5E%7B%2B%7D%5D%7D)
= 
= 
Now, pH will be calculated as follows.
pH = ![-log [H_{3}O^{+}]](https://tex.z-dn.net/?f=-log%20%5BH_%7B3%7DO%5E%7B%2B%7D%5D)
= 
= 5.59
Thus, we can conclude that pH at equivalence point for the given solution is 5.59.
<span>The combined gas equation relates three variables pressure, temperature and volume when the number of moles is constant.
The equation is PV / T = constant. Which is valid for a fixed number of moles of the gas.
You can derive the combined gas equation from the combination of Bolye's law, Charles' law and Gay-Lussac's law, which needs some algebra.
Answer: option 2. number of moles.
</span>
