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.
From the rate law, the information that is given by the rate constant is: C. It tells how much the reaction rate is affected by activation energy.
<h3>What is the rate law?</h3>Rate law is also referred to as rate equation and it can be defined as a chemical equation that is typically used to relate the initial (forward) chemical reaction rate with respect to the concentrations or pressures of the chemical reactants and constant parameters.
Mathematically, the rate law is given by this formula:
<u>Where:</u>
In Chemistry, the rate constant is typically used to tell the reaction rate or rate of a chemical reaction that is affected by activation energy.
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