Answer:
A- upfield
B- down field
C- splitting
D- chemical shift
E- integration
Explanation:
NMR is a spectroscopic technique commonly used to observe the magnetic fields around the nucleus of atoms in a compound under investigation.
A chemical shift is the difference in parts per million (ppm) between the resonance frequency of the observed protons in the compound under study and that of the tetramethylsilane (TMS) (the reference compound in NMR with a chemical shift of zero ppm because all protons in the compound are equivalent).
If signals appear close to the reference signal, the signals are said to appear upfield. If the signals appear far away from the reference, they are said to appear down field.
The presence of protons cause splitting of peaks to the magnitude of n+1. n is the number of neighboring protons. Splitting refers to the appearance of multiple peaks for a single nucleus due to neighboring nuclei.
The area of a signal that corresponds to the number of nuclei at that frequency is called the integration.
This problem is describing a gas mixture whose mole fraction of hexane in nitrogen is 0.58 and which is being fed to a condenser at 75 °C and 3.0 atm, obtaining a product at 3.0 atm and 20 °C, so that the removed heat from the system is required.
In this case, it is recommended to write the enthalpy for each substance as follows:
Whereas the specific heat of liquid and gaseous n-hexane are about 200 J/(mol*K) and 160 J/(mol*K) respectively, its condensation enthalpy is 31.5 kJ/mol, boiling point is 69 °C and the specific heat of gaseous nitrogen is about 29.1 J/(mol*K) according to the NIST data tables and 
and 
are the mole fractions in the gaseous mixture. Next, we proceed to the calculation of both heat terms as shown below:
It is seen that the heat released by the nitrogen is neglectable in comparison to n-hexanes, however, a rigorous calculation is being presented. Then, we add the previously calculated enthalpies to compute the amount of heat that is removed by the condenser:
Finally we convert this result to kJ:
Learn more:
Answer:
Determine the frequency of light with a wavelength of 2.775⋅10−7 cm. Answer in units of Hz?❤
Answer:
Correct answer is b) convex mirror
Explanation:
A convex mirror, which bulges outward, reflects at a wider angle near its edges than at its center, creating a slightly distorted image that's smaller than actual size. Convex mirrors have many uses. The smaller size of the images means that you can see more with these surfaces, hence their use in safety mirrors.
