Under which of the following reaction conditions,
Question: Under which of the following reaction conditions, aniline gives p-nitro derivative as the major product? (i) Acetyl chloride/pyridine followed by reaction with conc. H2SO4 + conc. HNO3 (ii) Acetic anhydride/pyridine followed by conc. H2SO4 + conc. HNO3 (iii) Dil. HCl followed by reaction with conc. H2SO4 + conc. HNO3 (iv) Reaction with conc. HNO3 + conc.H2SO4 Solution: Option (i) and (ii) are the answers....
Read More →Let *: R × R → R be a binary operation given
Question: Let $*: R \times R \rightarrow R$ be a binary operation given by $a * b=a+4 b^{2} .$ Then, compute $(-5) *(2 * 0)$ Solution: To find: $(-5) *(2 * 0)$ Given: $a^{*} b=a+4 b^{2}$ $\Rightarrow(2 * 0)=2+4 \times 0^{2}=2$ Now $(-5) * 2=-5+4 \times 2^{2}=-5+16=11$...
Read More →Evaluate the following integral:
Question: Evaluate the following integral: $\int \frac{3+4 x-x^{2}}{(x+2)(x-1)} d x$ Solution: First we simplify numerator, we get $\frac{3+4 x-x^{2}}{(x+2)(x-1)}$ $=\frac{-\left(x^{2}-4 x-3\right)}{x^{2}+x-2}$ $=\frac{-\left(x^{2}+x-5 x-2-1\right)}{x^{2}+x-2}$ $=\frac{-\left(x^{2}+x-2\right)}{x^{2}+x-2}+\frac{5 x+1}{x^{2}+x-2}$ $=-1+\frac{5 x+1}{(x+2)(x-1)}$ Now the denominator is factorized, so let separate the fraction through partial fraction, hence let $\frac{5 x+1}{(x+2)(x-1)}=\frac{A}{x+2...
Read More →Let * be a binary operation on the set of all nonzero real numbers, defined
Question: Let * be a binary operation on the set of all nonzero real numbers, defined by $a * b=\frac{a b}{5}$ Find the value of x given that2 * (x * 5) = 10. Solution: To find: value of $x$ Given: $a^{*} b=\frac{a b}{5}$ $\Rightarrow x^{* 5}=\frac{5 x}{5}=x$ Now $(2 * x)=\frac{2 x}{5}$ $\Rightarrow \frac{2 x}{5}=10 \Rightarrow x=25$...
Read More →Which of the following reactions
Question: Which of the following reactions are correct? Solution: Option (i) and (iii) are the answers....
Read More →The binary operation * on R is defined
Question: The binary operation $*$ on $\mathrm{R}$ is defined by $\mathrm{a} * \mathrm{~b}=2 \mathrm{a}+\mathrm{b}$. Find $(2 * 3) * 4$. Solution: To find: $(2 * 3) * 4$ Given: $a * b=2 a+b$ $\Rightarrow 2 * 3=2 \times 2+3=7$ Now $7 * 4=2 \times 7+4=14+4=18$ $\Rightarrow(2 * 3) * 4=18$...
Read More →Which of the following amines can
Question: Which of the following amines can be prepared by Gabriel synthesis. (i) Isobutyl amine (ii) 2-Phenylethylamine (iii) N-methyl benzylamine (iv) Aniline Solution: Option (i) and (ii) are the answers....
Read More →Arenium ion involved in the bromination
Question: Arenium ion involved in the bromination of aniline is __________. Solution: Option (i), (ii) and (iii) are the answers....
Read More →Evaluate the following integral:
Question: Evaluate the following integral: $\int \frac{x^{2}+x-1}{x^{2}+x-6} d x$ Solution: First we simplify numerator, we get $\frac{x^{2}+x-1}{x^{2}+x-6}$ $=\frac{x^{2}+x-6+5}{x^{2}+x-6}$ $=\frac{x^{2}+x-6}{x^{2}+x-6}+\frac{5}{x^{2}+x-6}$ $=1+\frac{5}{x^{2}+x-6}$ Now we will factorize denominator by splitting the middle term, we get $1+\frac{5}{x^{2}+x-6}$ $=1+\frac{5}{x^{2}+3 x-2 x-6}$ $=1+\frac{5}{x(x+3)-2(x+3)}$ $=1+\frac{5}{(x+3)(x-2)}$ Now the denominator is factorized, so let separate t...
Read More →The product of the following reaction
Question: The product of the following reaction is __________. Solution: Option (A) and (B) is the answer....
Read More →The reagents that can be used to convert benzene
Question: The reagents that can be used to convert benzene diazonium chloride to benzene are __________. (i) SnCl2/HCl (ii) CH3CH2OH (iii) H3PO2 (iv) LiAlH4 Solution: Option (ii)CH3CH2OH and (iii)H3PO2are the answers....
Read More →Which of the following species are involved
Question: Which of the following species are involved in the carbylamine test? (i) RNC (ii) CHCl3 (iii) COCl2 (iv) NaNO2 + HCl Solution: Option (i) and (ii) are the answers....
Read More →Reduction of nitrobenzene by
Question: Reduction of nitrobenzene by which of the following reagent gives aniline? (i) Sn/HCl (ii) Fe/HCl (iii) H2-Pd (iv) Sn/NH4OH Solution: Option (i), (ii) and (iii) are the answers....
Read More →Which of the following cannot be prepared
Question: Which of the following cannot be prepared by Sandmeyers reaction? (i) Chlorobenzene (ii) Bromobenzene (iii) Iodobenzene (iv) Fluorobenzene Solution: Option (iii)Iodobenzene and (iv)Fluorobenzeneare the answers....
Read More →Which of the following methods of preparation
Question: Which of the following methods of preparation of amines will not give the same number of carbon atoms in the chain of amines as in the reactant? (i) The reaction of nitrite with LiAlH4. (ii) The reaction of the amide with LiAlH4 followed by treatment with water. (iii) Heating alkyl halide with potassium salt of phthalimide followed by hydrolysis. (iv) Treatment of amide with bromine in the aqueous solution of sodium hydroxide. Solution: Option (iv) is the answer....
Read More →Which of the following should be most
Question: Which of the following should be most volatile? (i) II (ii) IV (iii) I (iv) III Solution: Option (ii)IVis the answer....
Read More →The correct decreasing order of basic strength
Question: The correct decreasing order of basic strength of the following species is _______. H2O, NH3, OH, NH2 (i) NH2 OH NH3 H2O (ii) OH NH2 H2O NH3 (iii) NH3 H2O NH2 OH (iv) H2O NH3 OH NH2 Solution: Option (i)NH2 OH NH3 H2O is the answer....
Read More →Evaluate the following integral:
Question: Evaluate the following integral: $\int \frac{1}{x(x-2)(x-4)} d x$ Solution: Here the denominator is already factored. So let $\frac{1}{x(x-2)(x-4)}=\frac{A}{x}+\frac{B}{x-2}+\frac{C}{x-4} \ldots \ldots(i)$ $\Rightarrow \frac{1}{x(x-2)(x-4)}=\frac{A(x-2)(x-4)+B x(x-4)+C x(x-2)}{x(x-2)(x-4)}$ $\Rightarrow 1=A(x-2)(x-4)+B x(x-4)+C x(x-2) \ldots \ldots$ (ii) We need to solve for A, B and C. One way to do this is to pick values for $x$ which will cancel each variable. Put $x=0$ in the above...
Read More →Among the following amines,
Question: Among the following amines, the strongest Brnsted base is __________. Solution: Option (iv) is the answer....
Read More →Which of the following compound will not undergo
Question: Which of the following compound will not undergo an azo coupling reaction with benzene diazonium chloride. (i) Aniline (ii) Phenol (iii) Anisole (iv) Nitrobenzene Solution: Option (iv)Nitrobenzene is the answer....
Read More →The best method for preparing primary amines
Question: The best method for preparing primary amines from alkyl halides without changing the number of carbon atoms in the chain is (i) Hoffmann Bromamide reaction (ii) Gabriel phthalimide synthesis (iii) Sandmeyer reaction (iv) Reaction with NH3 Solution: Option (ii)Gabriel phthalimide syntheis the answer....
Read More →The reaction Ar + N2Cl– → )Cu/HCl)– ArCl + N2 + CuCl
Question: The reaction Ar + N2Cl )Cu/HCl) ArCl + N2 + CuCl is named as _________. (i) Sandmeyer reaction (ii) Gatterman reaction (iii) Claisen reaction (iv) Carbylamine reaction Solution: Option (ii)Gatterman reaction is the answer....
Read More →Acid anhydrides on reaction with primary
Question: Acid anhydrides on reaction with primary amines give ____________. (i) amide (ii) imide (iii) secondary amine (iv) imine Solution: Option (i)amide is the answer...
Read More →Reduction of aromatic nitro compounds using
Question: Reduction of aromatic nitro compounds using Fe and HCl gives __________. (i) aromatic oxime (ii) aromatic hydrocarbon (iii) aromatic primary amine (iv) aromatic amide Solution: Option (iii) aromatic primary amine is the answer....
Read More →Let * be a binary operation on the set
Question: Let * be a binary operation on the set I of all integers, defined by a * b = 3a + 4b - 2. Find the value of 4 * 5. Solution: To find: 4*5 a*b = 3a + 4b - 2 Here a = 4 and b = 5 ⇒ 4*5 = 3 4 + 4 5 - 2 = 12 + 20 - 2 = 30 ⇒ 4*5 = 30...
Read More →