2-bromo-1-chloro-4-nitrobenzene is being synthesized in following sequence:
Step 1: Chlorination of Benzene:
This is Halogenation reaction of benzene. In this step benzene is reacted with Chlorine gas in the presence of lewis acid (i.e. FeCl₃). This results in the formation of Chlorobenzene as shown in red step below.
Step 2: Nitration of Chlorobenzene:
The chlorine atom on benzene has a ortho para directing effect. Therefore, the nitration of chlorobenzene will yield para nitro chlorobenzene as shown in blue step below.
Step 3: Bromination of 1-chloro-4-nitrobenzene:
In this step bromination is done by reacting bromine in the presence of lewis acid. The chlorine being ortho para directing in nature and nitro group being meta directing in nature will direct the incoming Br⁺ (electrophile) to the desired location. Hence, 2-bromo-1-chloro-4-nitrobenzene is synthesized in good yield.
Answer:

Explanation:
= Initial concentration = 1.28 M
= Final concentration = ![0.17[A]_0](https://tex.z-dn.net/?f=0.17%5BA%5D_0)
k = Rate constant = 0.0632 s
t = Time taken
For first order reaction we have the relation
![kt=\ln\dfrac{[A]_0}{[A]}\\\Rightarrow t=\dfrac{\ln\dfrac{[A]_0}{[A]}}{k}\\\Rightarrow t=\dfrac{\ln\dfrac{[A]_0}{0.17[A]_0}}{0.0632}\\\Rightarrow t=28.037\ \text{s}](https://tex.z-dn.net/?f=kt%3D%5Cln%5Cdfrac%7B%5BA%5D_0%7D%7B%5BA%5D%7D%5C%5C%5CRightarrow%20t%3D%5Cdfrac%7B%5Cln%5Cdfrac%7B%5BA%5D_0%7D%7B%5BA%5D%7D%7D%7Bk%7D%5C%5C%5CRightarrow%20t%3D%5Cdfrac%7B%5Cln%5Cdfrac%7B%5BA%5D_0%7D%7B0.17%5BA%5D_0%7D%7D%7B0.0632%7D%5C%5C%5CRightarrow%20t%3D28.037%5C%20%5Ctext%7Bs%7D)
Time taken to reach the required concentration would be
.
Answer:
Pure substances are made up of a bulk quantity of individual atoms or molecules.
Each pure substance is made up of one of Individual atoms of the same type that are connected to form extended structures.
A chemical reaction happens when substances break apart or combine to form one or more new substances.
- New substances form when bonds break and new bonds form.
The oxidizing agent is one which itself gets reduced and oxidizes other
Reduction : in this process the element accepts electron and gets reduced
Reducing agent is one which itself gets oxidized and reduces other
Oxidation : in this process the element loses electron and gets oxidized
Here the oxidation number of Sulphur change from -2 (FeS) to +6 (FeSO4) so it is oxidized and thus it is the reducing agent
The oxidation number of nitrogen changes from +5 (HNO3) to +2 (NO) thus it is reduced and thus it is the oxidizing agent
In the Permian period 250 million years ago we found the largest mass extinction where 95% of marine life and 70% of life on land becomes extinct.
Explanation:
In the geological time scale, the era of mesozoic was very important. It contained the period of Triassic Jurassic Cretaceous. There after neozoic era has come in which Permian and Carboniferous was important period. In Permian period many species becomes extinct.
Both marine and land species got extinct in this time period. Devastating natural disasters were responsible for this turmoil and caused loss of mass of species on the earth's surface. Severe volcanic eruption was one the factor behind this massive destruction.