Answer:
Nitrogen is one of the major abundant gas in the atmosphere occupying 78% by volume.
It plays an important role in controlling the aquatic and terrestrial ecosystem. The presence of high amount of nitrogen in the atmosphere can lead to the release of large amount of pollutants that includes ammonia and ozone, which can cause difficulty in breathing, visibility problems and at the same time, it will also the affect the growth and expansion of plants. It also can damages to the forests, soils, and water.
The presence of extremely large amount of nitrogen gas in the aquatic ecosystem can also influence the growth of aquatic plants and algae. When these organisms are present in a large number then it blocks the water in-taking path of these plants. It eventually consumes the dissolved oxygen as soon as they decompose, as a result of which it does not allow the light to penetrate into the deeper water (zones).
Total internal energy change is equals to -44.83kJ
Q=-73.2kJ (negative sign indicates that heat was released by the system),
P= 50.0atm
ΔU= Q + W, FIRST LAW OF THERMODYNAMICS..........(1)
ΔV= Final volume - initial volume= 2.00 litre - 7.60litre= -5.60litre
work done by the system (w)= -PΔV
w= -(50.0×(-5.60)) atm×litre= 280atm litre
1 atm litre= 101.325J
w= 280 ×101.325 J= 28,371J
1kJ=1000J,
w=28.37KJ,
so putting in the values in equation (1)...
energy change(ΔU) = -73.2 kJ + 28.37 kJ
= - 44.83 kJ
To know this you pretty much do have to kind of memorize a few electronegativities. I don't recall ever getting a table of electronegativities on an exam.
From the structure, you have:
I remember the following electronegativities most because they are fairly patterned:
EN
H
=
2.1
EN
C
=
2.5
EN
N
=
3.0
EN
O
=
3.5
EN
F
=
4.0
EN
Cl
=
3.5
Notice how carbon through fluorine go in increments of
~
0.5
. I believe Pauling made it that way when he determined electronegativities in the '30s.
Δ
EN
C
−
Cl
=
1.0
Δ
EN
C
−
H
=
0.4
Δ
EN
C
−
C
=
0.0
Δ
EN
C
−
O
=
1.0
Δ
EN
O
−
H
=
1.4
So naturally, with the greatest electronegativity difference of
4.0
−
2.5
=
1.5
, the
C
−
F
bond is most polar, i.e. that bond's electron distribution is the most drawn towards the more electronegative compound as compared to the rest.
When the electron distribution is polarized and drawn towards a more electronegative atom, the less electronegative atom has to move inwards because its nucleus was previously favorably attracted to the electrons from the other atom.
That means generally, the greater the electronegativity difference between two atoms is, the shorter you can expect the bond to be, insofar as the electronegative atom is the same size as another comparable electronegative atom.
However, examining actual data, we would see that on average, in conditions without other bond polarizations occuring:
r
C
−
Cl
≈
177 pm
r
C
−
C
≈
154 pm
r
C
−
O
≈
143 pm
r
C
−
F
≈
135 pm
r
C
−
H
≈
109 pm
r
O
−
H
≈
96 pm
So it is not necessarily the least electronegativity difference that gives the longest bond.
Therefore, you cannot simply consider electronegativity. Examining the radii of the atoms, you should notice that chlorine is the biggest atom in the compound.
r
Cl
≈
79 pm
r
C
≈
70 pm
r
H
≈
53 pm
r
O
≈
60 pm
So assuming the answer is truly
C
−
C
, what would have to hold true is that:
The
C
−
F
bond polarization makes the carbon more electropositive (which is true).
The now more electropositive carbon wishes to attract bonding pairs from chlorine closer, thereby shortening the
C
−
Cl
bond, and potentially the
C
−
H
bond (which is probably true).
The shortening of the
C
−
Cl
bond is somehow enough to be shorter than the
C
−
C
bond (this is debatable).
Answer:
ik this isnt the answer but mathwa will solve all yours problems
Explanation:
Entropy change of vaporization is simply the ratio of
enthalpy change and the temperature in Kelvin.
Temperature = 64 + 273.15 = 337.15 K
Hence,
δsvap = (32.21 kJ / mole) / 337.15 K
<span>δsvap = 0.0955 kJ / mole K = 95.5 J / mole K</span>