Answer:
A) 1059 J/mol
B) 17,920 J/mol
Explanation:
Given that:
Cp = 29.42 - (2.170*10^-3 ) T + (0.0582*10^-5 ) T2 + (1.305*10^-8 ) T3 – (0.823*10^-11) T4
R (constant) = 8.314
We know that:

We can determine
from above if we make
the subject of the formula as:




A).
The formula for calculating change in internal energy is given as:

If we integrate above data into the equation; it implies that:



Hence, the internal energy that must be added to nitrogen in order to increase its temperature from 450 to 500 K = 1059 J/mol.
B).
If we repeat part A for an initial temperature of 273 K and final temperature of 1073 K.
then T = 273 K & T2 = 1073 K
∴



A pi bond is a bond formed by the overlap of orbitals in a side-by-side fashion with the electron density concentrated above and below the plane of the nuclei of the bonding atoms. ... Three sigma bonds are formed from each carbon atom for a total of six sigma bonds total in the molecule.
Answer: Molecular mass of the phenol is 94g/mol.
Explanation:
Phenol is an active ingredient in some oral anesthetics used in sore throat sprays.It is used as anesthetics to cure minor sour throat pain , minor mouth irritations etc.
For Example : Cramex , Chloraseptic sprays contains phenol as an active ingredient.
Phenol has a molecular formula of 
Molecular mass of the phenol = 6(mass of carbon)+5(mass of hydrogen)+1(mass of oxygen)+1(mass of hydrogen) = 6(12)+5(1)+1(16)+(1) = 94 g/mol
Answer:An endothermic reaction
Explanation: In an endothermic reaction, it takes more energy to break the bonds of the reactants than is released when the bonds in the products are formed. In an endothermic reaction, the temperature goes down.