Answer:
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Explanation:
Answer:
n=1 holds two electrons and n=2 holds eight electrons.
Explanation:
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In this case, since the atomic number of aluminum is 13, its electron configuration is:

In such a way, we can see that the level n=1 is filled with two electrons since the subshell s is able to hold two electrons and the level n=2 is also filled but with eight electrons as s holds two whereas p holds 6. Moreover, n=3 is holding three electrons.
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Answer:
Kₐ = 6.7 x 10⁻⁴
Explanation:
First lets write the equilibrium expression, Ka , for the dissociation of hydrofluoric acid:
HF + H₂O ⇄ H₃O⁺ + F⁻
Kₐ = [ H₃O⁺ ] [ F⁻ ] /[ [ HF ]
Since we are given the pH we can calculate the [ H₃O⁺ ] ( pH = - log [ H₃O⁺ ] , and because the acid dissociates into a 1: 1 relation , we will also have [F⁻ ]. The [ HF ] is given in the question so we have all the information that is needed to compute Kₐ.
pH = -log [ H₃O⁺ ]
1.68 = - log [ H₃O⁺ ]
Taking antilog to both sides of this equation:
10^-1.68 = [ H₃O⁺ ] ⇒ 2.1 X 10⁻² M= [ H₃O⁺ ]
[ F⁻ ] = 2.1 X 10⁻² M
Solving for Kₐ :
Kₐ = ( 2.1 X 10⁻² ) x ( 2.1 X 10⁻² ) / 0.65 = 6.7 x 10⁻⁴
(Rounded to two significant figures, the powers of 10 have infinite precision )
Answer:
Sand
Explanation:
with salt distillation will work, heat the solution and collect the water in a seperate beaker
With sugar you do the same, boil away the water and collect the water vapour, you'll be left with sugar in the original container and water if you collected it
Use a fraction of column and heat the solution, the alcohol will be seperated out
Sand is the only one that uses mechanical filtration
The correct answer is B) Chlorine, Sulfur, and Silicon
I'm 100% sure this is correct
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