All the elements in one group have the same number of valence electrons.
Answer:
A)21
Explanation:
To know the difference between the number of electrons in the two atoms, we must first know the number of electrons in the atoms.
For Selenium, Se, we have 34 electrons. The element is in group 6 on the periodic table.
Aluminum on the other hand is in the Boron family with a total of 13 electrons.
The difference,( 34-13) electrons gives a total of 21 electrons
Answer:
The study is called ecology
Explanation:
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Answer: At equilibrium, the partial pressure of 
is 0.0330 atm.
Explanation:
The partial pressure of is equal to the partial pressure of 
. Hence, let us assume that x quantity of 
is decomposed and gives x quantity of and x quantity of .
Therefore, at equilibrium the species along with their partial pressures are as follows.
At equilibrium: 0.123-x x x
Now, expression for 
of this reaction is as follows.
![K_{p} = \frac{[PCl_{3}][Cl_{2}]}{[PCl_{5}]}\\0.0121 = \frac{x \times x}{(0.123 - x)}\\x = 0.0330](https://tex.z-dn.net/?f=K_%7Bp%7D%20%3D%20%5Cfrac%7B%5BPCl_%7B3%7D%5D%5BCl_%7B2%7D%5D%7D%7B%5BPCl_%7B5%7D%5D%7D%5C%5C0.0121%20%3D%20%5Cfrac%7Bx%20%5Ctimes%20x%7D%7B%280.123%20-%20x%29%7D%5C%5Cx%20%3D%200.0330)
Thus, we can conclude that at equilibrium, the partial pressure of is 0.0330 atm.
