No of Neutrons =Mass No-No of protons


- Hence it has atomic no 38
The element is Stroncium(Sr)
55= No (1/2)^55/57
55= No (1/2)^3.9
55= No (1/2)^4
55= No (1/16)
No= 880 g
Answer:
p-fluoronitrobenzene and sodium phenoxide is more appropriate
Explanation:
An ipso substitution is required to form p-nitrophenyl phenyl ether.
For this ipso substitution, an alkoxide anion needs to attack as a nucleophile at the carbon atom attached to fluorine atom and thereby substitute that F atom.
p-nitrophenoxide is an weak nucleophile as compared to phenoxide due to presence of electron withdrawing resonating effect of nitro group at para position.
p-fluoronitrobenzene is a good choice for nucleophilic attack by alkoxide anion as compared to fluorobenzene due to higher positive charge density at carbon atom directly attached to F atom. Higher positive charge density arises due to presence of electron withdrawing resonating effect og nitro group at para position.
So, p-fluoronitrobenzene and sodium phenoxide is more appropriate
The molar extinction coefficient is 15,200
.
The formula to be used to calculate molar extinction coefficient is -
A = ξcl, where A represents absorption, ξ refers molar extinction coefficient, c refers to concentration and l represents length.
The given values are in required units, hence, there is no need to convert them. Directly keeping the values in formula to find the value of molar extinction coefficient.
Rewriting the formula as per molar extinction coefficient -
ξ = 
ξ = 
Performing multiplication in denominator to find the value of molar extinction coefficient
ξ =
Performing division to find the value of molar extinction coefficient
ξ = 15,200 
Hence, the molar extinction coefficient is 15,200
.
Learn more about molar extinction coefficient -
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