#ug-chemistry

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pearl isle
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Help please..

3)For the description of the covalent bond and the structure of the molecules can be used the theory of noble gases, the theory of valence bonds and the theory of molecular orbitals.
(a) Describe the oxygen molecule (make the structure) in the light of the noble gas theory.
(b) Describe the oxygen molecule and the nitrogen molecule in the light of the theory of molecular orbitals.
(c) Why is oxygen paramagnetic and nitrogen diamagnetic?
(d) Which of the molecules is more stable? Why?

frosty ferryBOT
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dry lynx
# pearl isle Help please.. 3)For the description of the covalent bond and the structure of t...

for 3a: u shud probably describe the noble gas theory (octet rule) first then talk ab the oxygen question part which is like the oxygen atom has 6 valence electrons, and they need 2 more electrons to achieve a full outer shell and so, In the oxygen molecule: the two oxygen atoms share a double bond (where each atom contributing 2 electrons to the bond). Therefore both oxygen atoms will have that full outer shell of 8 electrons and so it satisfies the octet rule.

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for 3b: we focus on 2s and 2p orbitals
Oxygen molecule (O2):

-Two 2s atomic orbitals combine to form one sigma(2s) bonding orbital and one sigma.(2s) antibonding orbital.
-Six 2p atomic orbitals combine to form one sigma(2p) bonding orbital, two pi(2p) bonding orbitals, one sigma . (2p) antibonding orbital, and two pi . (2p) antibonding orbitals.
-Intotal, O2 has 12 valence electrons to fill these molecular orbitals.
molecular orbital configuration = σ(2s)^2, σ.(2s)^2, σ(2p)^2, π(2p)^4, π.(2p)^2.

Nitrogen molecule (N2):

-Two 2s atomic orbitals combine to form one sigma(2s) bonding orbital and one sigma.(2s) antibonding orbital.
-Six 2p atomic orbitals combine to form one sigma(2p) bonding orbital, two pi(2p) bonding orbitals, one sigma.(2p) antibonding orbital, and two pi.(2p) antibonding orbitals.
-In total, N2 has 10 valence electrons to fill these molecular orbitals.
molecular orbital configuration = σ(2s)^2, σ.(2s)^2, σ(2p)^2, π(2p)^4, π.(2p)^0.

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then for 3c:
oxygen: it has unpaired electrons in its molecular orbitals cuz two unpaired electrons in the π*(2p) antibonding orbitals
nitrogen: all of its electrons are paired in its molecular orbitals

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3d: nitrogen molecules is more stable than oxygen molecules. Because in N2 all bonding orbitals are filled and no electrons in antibonding orbitals leading to stronger bond (triple). O2, there are electrons in the π*(2p) antibonding orbitals, which weakens the bond (double) and so less stable compared to N2.

dry lynx
pearl isle
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Wow...thanks a lot
It really helped cz i had a faint idea of what the question required but didn't know how to structure it

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+++it sounds right to me☺

gentle vector
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Hi

willow quiver
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Hi guys!

Does anyone know where one could find “a Science paper marking” job on the internet?

pearl isle
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Hello Guys!Any help is appreciated!

At 150oC a given reaction ends in 16 minutes. Knowing that the thermal coefficient of the velocity is 2,5, calculate the time it takes for this same reaction to end if it occurs at: a) 200 °C; b) to 80°C

unborn island
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@wild sage

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Sowwi for ze delay

wild sage
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thx

ripe swallow
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this channel actually exists

wild sage
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it sure does

wild sage
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@ripe swallow sry for ping but ur the only one here i know can solve this

unknown.png
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what would I do here

dense vale
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heyyy i know this isn't ideal but i really need help with this
An unknown compound is found to have the following stable isotopes:

Isotope Atomic Mass (amu) Percent Abundance (%)
X-1 27.884 92.21
X-2 28.97649 4.70
X-3 29.97376 3.09
Determine the weighted-average atomic mass for this compound.

pliant quarryBOT
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golden dove
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Anyone have pdf of this book?
Vogel's Textbook of Quantitative Chemical 6th Edition

frosty ferryBOT
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