Answer is:
18 electrons.
<span>The principal quantum number (n) is one
of four quantum numbers which are assigned to each electron in an atom to
describe that electron's state.
The azimuthal quantum number (l) is a quantum number for
an atomic orbital that determines its orbital angular
momentum and describes the shape of the orbital, l = 0....n-1.</span>
<span>For n = 3, l = 0, 1, 2.</span>
<span>l = 0, s orbital with 2 electron.</span>
<span>l = 1, p orbitals with 6 electrons.</span>
<span>l = 2, d orbitals with 10 electrons.</span>
<span>2 + 6 + 10 = 18 electrons.</span>
It will take 497.67 years to decay.
What is half-life ?
The duration needed for a quantity to decrease to half of its initial value is known as the half-life. In nuclear physics, the phrase is frequently used to indicate how rapidly unstable atoms decay radioactively or how long stable atoms last. The phrase is also used more broadly to describe any kind of exponential decay (or, very infrequently, nonexponential decay). The biological half-life of medications and other compounds in the human body, for instance, is a term used in the medical sciences. Half-opposite life's in exponential growth is time's doubling.
The formula
At = (Ao)(0.5)(t/h)
where Ao is the initial amount determines the amount of material at a specific time t, At, with a half-life of h.
At/Ao = 0.45 from the stated results in (0.5)(t/432).
T in the equation has a value of 497.67 years.
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Answer:
74 g/mol
Explanation:
Using a periodic table, we can determine the molar mass by adding together 1 Ca, 2 O, and 2 H. This turns out to be approximately (40+32+2) = 74 g/mol
Answer: it C
Explanation: Because is the only that makes sense and the only one that seems right
