First find the oxidation states of the various atoms:
<span>in Cr2O2 2- Cr @ +1; In NH3 N @ +3; in CrO3 Cr @ +3, N2 N @ 0 </span>
<span>Note that N gained electrons, ie, was reduced; Cr was oxidized </span>
<span>Now there is a problem, because B has NH4+ which the problem did not, and is not balanced, showing e- in/out </span>
<span>B.NH4+ → N2 </span>
<span>Which of the following is an oxidation half-reaction? </span>
<span>A.Sn 2+ →Sn 4+ + 2e- </span>
<span>Sn lost electrons so it got oxidized</span>
It is simple. A plant structure have different parts but both structures carry around an Cell Wall.
The mass number of an atom is its total number of protons and neutrons. Atoms of different elements usually have different mass numbers , but they can be the same. For example, the mass number of argon atoms and calcium atoms can both be 40.
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.
To learn more about half-life click on the link below:
brainly.com/question/19500804
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