1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p1
Primero realizas la configuración electrónica que es la que te puse allá arriba.
Después miras el nivel en que termina, puede ser 1, 2, 3, 4 etc.
Entonces como el último número de la configuración electrónica es 4, entonces ese es el nivel
Y los electrones de el último nivel son los de Valencia
4s2, 4p1 sumas 2+1 que son los electrones que se encuentran en el último nivel.
por eso hay 3 electrones de valencia.
Answer:
0.2024 M
Explanation:
For the decomposition reactio given, let's do an equilibrium chart. Let's call the initial concentration of NH₃ as C:
2NH₃(g) ⇄ N₂(g) + 3H₂(g)
C 0 0 Initial
-2x +x +3x Reacts (stoichiometry is 1:1:3)
C - 2x x 3x Equilibrium
3x = 0.252
x = 0.084 M
The equilibrium constant (Kc) is the multiplication of the concentrations of the products elevated by their coefficients, divided by the multiplication of reactants concentrations elevated by their coefficients.
Kc = ([H₂]³*[N₂])/([NH₃]²)
4.50 = [(0.252)³*(0.084)]/(C - 2*0.084)²
4.50 = 0.00533/(C - 0.168)²
4.50 = 0.00533/(C² - 0.336C + 0.028224)
4.50C² - 1.512C + 0.127008 = 0.00533
4.50C² - 1.512C + 0.121678 = 0
Solving the equation by a graphic calculator, for C > 0.168
C = 0.2024 M
Because they have a full outer shell and they are both noble gases...Because the outer shell has attained stable electronics configuration of octate rule this it is with noble gas as helium.
Hope I helped!
1. 
- The changing of liquid to a gas.
2. 
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3. 
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4. 
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5. 
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6. 
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