4 is correct for this one
Answer:
Here
Explanation:
When the atom absorbs energy, it can move to a higher energy state, or excited state. Under what circumstances can an atom emit a photon? A photon is emitted when an atom moves from an excited state to its ground state or to a lower-energy excited state.
The question is incomplete, the complete question is;
Identify the highest energy molecular process that occurs when a molecule absorbs a microwave photon
a) electronic excitation
b) bond breakage
c) molecular vibration
d) molecular rotation
Answer:
molecular rotation
Explanation:
Microwaves are part of the electromagnetic spectrum. They are lower energy, lower frequency radiation.
When molecules absorb infrared radiation, they transition between the rotational states of the molecule.
Hence, the highest energy molecular process that occurs when a molecule absorbs a microwave photon is molecular rotation.
Hi, the question has some missing part. The complete question should be " If the 
of 
is 3.74 and the pH of an 
solution is 3.89, it means that -
(a) ![[HCHO_{2}]=[NaCHO_{2}]](https://tex.z-dn.net/?f=%5BHCHO_%7B2%7D%5D%3D%5BNaCHO_%7B2%7D%5D)
(b) ![[HCHO_{2}]> [NaCHO_{2}]](https://tex.z-dn.net/?f=%5BHCHO_%7B2%7D%5D%3E%20%5BNaCHO_%7B2%7D%5D)
(c) ![[HCHO_{2}]< [NaCHO_{2}]](https://tex.z-dn.net/?f=%5BHCHO_%7B2%7D%5D%3C%20%20%5BNaCHO_%7B2%7D%5D)
Which of the options are true?"
Answer: Option (c) is true.
Explanation:
is an weak acid-conjugate base buffer. Hence, in accordance with Henderson-Hasselbalch equation-
![pH=pK_{a}(HCHO_{2})+log(\frac{[CHO_{2}^{-}]}{[HCHO_{2}]})](https://tex.z-dn.net/?f=pH%3DpK_%7Ba%7D%28HCHO_%7B2%7D%29%2Blog%28%5Cfrac%7B%5BCHO_%7B2%7D%5E%7B-%7D%5D%7D%7B%5BHCHO_%7B2%7D%5D%7D%29)
Here, pH = 3.89, of = 3.74
So, ![3.89=3.74+log(\frac{[CHO_{2}^{-}]}{[HCHO_{2}]})](https://tex.z-dn.net/?f=3.89%3D3.74%2Blog%28%5Cfrac%7B%5BCHO_%7B2%7D%5E%7B-%7D%5D%7D%7B%5BHCHO_%7B2%7D%5D%7D%29)
or, ![\frac{[CHO_{2}^{-}]}{[HCHO_{2}]}](https://tex.z-dn.net/?f=%5Cfrac%7B%5BCHO_%7B2%7D%5E%7B-%7D%5D%7D%7B%5BHCHO_%7B2%7D%5D%7D)
= 1.41 (>1)
So, ![[CHO_{2}^{-}]> [HCHO_{2}]](https://tex.z-dn.net/?f=%5BCHO_%7B2%7D%5E%7B-%7D%5D%3E%20%5BHCHO_%7B2%7D%5D)
or, ![[NaCHO_{2}]> [HCHO_{2}]](https://tex.z-dn.net/?f=%5BNaCHO_%7B2%7D%5D%3E%20%5BHCHO_%7B2%7D%5D)
Hence, option (c) is correct.
