Answer:
7 valence electrons
Explanation:
Astatine has the atomic number 85. Thus, its electron configuration is:
[Xe] 4f¹⁴ 5d¹⁰ 6s² 6p⁵
As we can see, in the last level (6) it has 2 + 5 = 7 electrons, that is, astatine has 7 electrons in its valence shell. In the Lewis dot structure (attached) we write 3 pairs of electrons and 1 unpaired electron around the symbol of At.
Answer:
organs is the right answer
Molar mass KCl = 74.55 g/mol
Number of moles:
mass KC / molar mass
149 / 74.55 => 1.998 moles
Volume in liters: 500 mL / 1000 => 0.5 L
Therefore:
M = moles / volume
M = 1.998 / 0.5
M = 3.996 mol/L⁻¹
Answer:
Five Types of Introductions.
“Inquisitive” Explain why your subject is important, curious, or interesting.
“Paradoxical” Explain what aspects of your subject seem improbable. ...
“Corrective” Explain how your subject has been misunderstood or misrepresented by others. ...
Answer: 
Explanation:
Equilibrium constant is defined as the ratio of concentration of products to the concentration of reactants each raised to the power their stoichiometric ratios. It is expressed as 
The expression for is given as:
![K_{eq}=\frac{[NOBr]^2}{[NO]^2[Br_2]}](https://tex.z-dn.net/?f=K_%7Beq%7D%3D%5Cfrac%7B%5BNOBr%5D%5E2%7D%7B%5BNO%5D%5E2%5BBr_2%5D%7D)
Thus in the reaction, 
has to be product and 
and 
has to be reactants, the reaction has to be
