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A molecule of diatomic hydrogen (hydrogen gas) contains two hydrogen atoms. The nucleus of each aton (a protron) is spinning. Depending upon the direction of the spin of the two nuclei, the hydrogens are of two types: ortho or para.
Ortho-hydrogen molecules are those in which the spins of both the nuclei are in the same direction. Para-hydrogen is when the spins of both the nuclei are in the opposite directions. Ordinary hydrogen gas is an equilibrium mixture of ortho and para hydrogen. The amount of ortho- and para-hydrogen varies with temperature.
At 0°K, hydrogen contains mainly para-hydrogen which is more stable. At the temperature of liquid of air, the ratio of ortho- and para-hydrogen is 1 : 1.
At the room temperature, the ratio of ortho- to para-hydrogen is at its maximum of 3 : 1. Even at very high temperatures, the ratio of ortho- to para-hydrogen can never be more than 3 : 1. So, it is possible to get pure para hydrogen by cooling ordinary hydrogen gas to a very low temperature (close to 20 K) but it is never possible to get a sample of hydrogen containing more than 75% of ortho hydrogen.
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Which is a pair of allotropes?
Yes ofcourse Hydrogen have two allotropes, Ortho hydrogen and para hydrogen. They differ only in having parallel and anti parallel nuclear spins. It was first observed by Heisenberg in 1927. BY RAJESH KUMAR GDC MPM SINDH PAKISTAN
What is the reaction of phenol with Bromine?
The hydroxyl group in phenol is an activating ortho/para director, but has some slight steric hindrance too ortho position substitution. Therefore, the predominant product of reaction between phenol and bromine will be 4-bromophenol, if reaction conditions are carefully controlled. With excess bromine, di- and tri-bromo phenols will be formed.
What is the name of Na3PO3?
The compound with formula Na3PO4 is named "sodium phosphate", "trisodium phosphate", "sodium ortho-phosphate", or "trisodium ortho-phosphate".
What is the most likely site of iodination in an iodination of salicylamide experiment and why?
I guess you could end up with either a 1,2,3-trisubstituted or 1,2,4-trisubstituted ring, but the main product in my experiment was 2-hydroxy-5-iodobenzamide (a 1,2,4-trisubstituted ring) determined by the ortho/para-directing hydroxyl group at the C1 carbon, coupled with the meta-directing amide at the C2 (both directing substitution to the C4 position), and then narrowed down to a specific position by the 816.28 cm^-1 strong peak that was on the fingerprint region of my IR spectra that is characteristic of a 1,2,4-trisubstituted ring. Also, if you draw out the carbocation intermediates you can see that the positive charge would not end up on the C2, which is the most likely scenario when you consider the C2 is already partially positive due to the electron withdrawing amide that is attached to it.
How many sets of equivalent hydrogen are there in the compound 2-methylpropane?
3
What are the differences between ortho hydrogen and para hydrogen?
Positioning around a benzene ring relative to the major functional group. Para is opposite, ortho is next to, meta is in between.
Ortho - hydroxyacetophenone vs para - hydroxyacetophenone polarity?
para is more polar than the ortho
Why toulene is ortho and para directing?
Toluene is an aromatic compound, generally it under goes electrophilic substitution reactions i.e. usually one of the hydrogen, is replaced by an electrophile. It increases the electron density at ortho and para position only not at meta. So electrophile attacks at ortho and para position. Ex. Nitration of Toluene
Why methyl attached to benzene is ortho-para director group?
This group attached to benzene ring acts as the ortho-para directing group due to Hyperconjugation.
Why is orthonitro phenol more volatile than its corresponding meta and para isomers?
Since there is intramolecular hydrogen bonding between -OH and -NO2 groups, present in the ORTHO-nitrophenol (they are very close to each other), these ortho-molecules do NOT attrack each other so much by intermolecular forces caused by hydrogen bonding as is the case with meta- and para-nitrophenol.
What is ortho meta and para in benzene?
ortho-para in benzene is meaningless these positions are for monosubstituted benzene. Meta is positions 3 and 5. Ortho is position 2 and 6 with relation to already attached group, para is 4 (opposite) to attached group.
How do you separate ortho and para nitro phenol?
by steam distillation as o-nitrophenol is volatile due to intra-molecular hydrogen bonding, SYNCRO, GKP
Why halogens that is deactivate group attack to ortho and para position?
Because of mesomeric effect, the electron density on the ortho and para positions for the aromatic ring is more.
What are the examples of Ortho and para directing group and mata directing group?
Electrophilic Aromatic Substitution is an example of Ortho and para directing group and meta directing group.
Which is a pair of allotropes?
Yes ofcourse Hydrogen have two allotropes, Ortho hydrogen and para hydrogen. They differ only in having parallel and anti parallel nuclear spins. It was first observed by Heisenberg in 1927. BY RAJESH KUMAR GDC MPM SINDH PAKISTAN
What is the ortho-peradirective nature?
I think you're asking about ortho-para directors. o,p directors are groups bonded to a benzene ring that direct additional groups in electrophilic aromatic substitution reactions to attach to the ortho and para positions of the benzene ring. Ortho is the position next to the group and para is the position across from the group on the benzene ring. o,p directors are electron donating groups such as methoxy groups. These groups stabilize the positive charge created in the intermediate when the electrophile adds to the ortho and para positions. o,p directors do not, however, stabilize the positive charge when the electrophile adds to the meta position and therefore only allow addition to the ortho and para positions (thus the name ortho-para director).
Activating and deactivating group of Ortho para and meta director groups Explain?
You can either deactivate or activate the group of Ortho para and Meta director groups depending with your preference.
