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
![ln [\frac{5.8 * 10^{3}}{2.2 *10^{5}} ] = - \lambda * 20235](https://tex.z-dn.net/?f=ln%20%5B%5Cfrac%7B5.8%20%2A%2010%5E%7B3%7D%7D%7B2.2%20%2A10%5E%7B5%7D%7D%20%5D%20%3D%20-%20%20%5Clambda%20%2A%2020235)
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.
