An animal skeleton has a carbon-14 decay rate of 13.1 disintegrations per minute per gram of carbon. when did the animal die? (assume that living organisms have a carbon-14 decay rate of 15.3 disintegrations per minute per gram and that carbon-14 has a half-life of 5730yrs.)

1034 yrs

Explanation:

The equation to use in this question is:

t = -2.303/k log (A/A₀) where

A=    present number of disintegrations

A₀ =  intial number of disintegrations

k =  decay constant

The decay constant we will obtain it from the given hal-life:

k: 0.693/t₁/₂,        t₁/₂ = half-life   ⇒

k: 0.693 / 5730 y =  1.209 x 10⁻⁴ /y⁻¹

t = - 2.303 / 1.209 x 10⁻⁴ /y⁻¹ x log (13.1/15.3) =  1034 yrs

answer:

the answer is 6 valence electrons.

explanation:

valence is the # of electrons on the outer most shell of an atom.

oxygen has 6.

although, the valency of oxygen is 2, because it only needs to make 2 covalent bonds, or gain 2 electrons, to achieve the stable octet configuration of a noble gas.

that's it!

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~ trueboss72