How many different sets of equivalent protons are there for para-xylene (1,4-dimethylbenzene)? only 1 two three four?
1 answer:
Answer:
Two
Step-by-step explanation:
There are two ways to determine the number sets of equivalent protons in a compound.
(a) By substitution
Replace each H with a different group and see if you get a different compound
For example, the six CH₃ H atoms are an equivalent set, because, if I replace any one of them, I will always get the same compound: 1-chloromethyl-4-methylbenzene (Fig. 1).
Similarly, the four aromatic H atoms are an equivalent set. If I replace any one of them, I will always get the same compound: 2-chloro-1,4-dimethylbenzene (Fig. 2).
Thus, there are two sets of equivalent protons in p-xylene.
(b) By symmetry
Two atoms are equivalent if one can be converted into the other by a <em>symmetry operation</em> on the molecule.
The methyl hydrogens can be interconverted by a combination of <em>reflections</em> about the AB and CD mirror planes and by<em> </em><em>rotation</em>s about the C-C bonds to the ring (Fig. 3).
Similarly, the four aromatic H atoms can be interconverted by a combination of <em>reflections</em> about the AB and CD mirror planes.
Again, we find two sets of equivalent protons.
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<u>Answer:</u> Oxidation state of Arsenic in the given compound is +3 and that of oxygen is -2.
<u>Explanation:</u>
We are given a compound having formula and we need to find the oxidation state of all the atoms in this compound. There are 2 different atoms present in this : Arsenic and Oxygen
Oxidation state is the number which is assigned to an element in a compound which represents the number of electrons lost or gained by an atom in a compound.
Oxidation state of oxygen as -2 which is same always. Now, to calculate the oxidation state of Arsenic, we take the oxidation state of it be 'x'
As, there are two arsenic atoms and three oxygen atoms, then:
Hence, oxidation state of Arsenic in the given compound is +3 and that of oxygen is -2.