Zero ( If the number of electrons equal of the protons in an atom.
Answer:
19656J
Explanation:
Step 1:
Data obtained from the question.
Mass (M) = 78g
Initial temperature (T1) = 20°C
Final temperature (T2) = 80°C
Change in temperature (ΔT) = T2 – T1 =
80°C – 20°C = 60°C
Specific heat capacity (C) = 4.2J/g°C
Heat (Q) =...?
Step 2:
Determination of the heat required for the reaction.
Q = MCΔT
Q = 78 x 4.2 x 60
Q = 19656J
Therefore, 19656J of heat is required.
<span>Mass of nitrogen = 14.0067
</span>
Mass of oxygen = 15.9994
In this compound nitrogen = 36.86 /
14.0067 = 2.63
<span>And oxygen = 63.14 / 15.9994 = 3.95 <span>
now we have: N----- 2.63 and O----3.95
by dividing both with the smallest number we get
</span></span>
<span>N-------2.63/2.63 = 1<span>
<span>O-------3.95/2.63 = 1.5
To get whole numbers we multiply both by 2
</span></span></span>
N= 1 x 2 = 2
And O = 1.5 x 2= 3
<span>So, the empirical formula is N</span>₂O₃.
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.
