The correct answer is option C
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Carbon monoxide<span>, lead, </span>nitrogen dioxide<span>, </span>ozone<span>, particulate matter, and </span>sulfur dioxide
Answer:
The half-life is 
Explanation:
From the question we are told that
The sample is 90 Y
The first activity is
per minute
The second activity is
per minute
The duration from 1:00 p.m. on December 3, 2006 to 2:15 p.m. on December 17, 2006 is

Converting to minutes we have


The first order rate constant for this disintegrations can be mathematically represented as

Where
is the rate constant
Substituting values

So


The half life is mathematically represented as

So 

Answer:
.Electron affinity is -142 kJ<---------->O(g)+e−→O−(g)Process involves single electron addition
O−(g)+e−→O2−(g)<--------> Electron affinity is +710 kJ. .Process is endothermic
Cl(g)+e−→Cl−(g)=Electron affinity is -349 kJ. Process involves single electron addition
None of the of thee reactions ----------Electron affinity is +142 kJ.
Explanation:
Negative electron affinity values indicate that energy is given out when the atom accepts an electron. Halogens evolve a large amount of heat on forming halide ions.
Substantial amount of energy is absorbed when two electrons are added to O2- thus its electron affinity has a positive sign. Energy is evolved on adding only one electron to form O- is hence it has a negative value of electron affinity as shown.