datavorous/entrance-exam-dataset huggingface dataset:
An object of mass 5 kg and speed 10 m s-1 explodes into two pieces of equal mass. One-piece comes to rest. The kinetic energy added to the system during the explosion is

Options:
A zero
B 50Â J
C 250 J
D 500Â J

The correct answer is:
250 J

Solution:
According to conservation of momentum mu=m2×0+m2v
⇒v=2u
⇒v= 2×10=20 m s-1
⇒KEi=12mu2
⇒KEi=12×5×102
⇒KEi=250 J
Now KEg=12×m2v2
⇒KEg=12×52×202
⇒KEg=500 J
Additional energy is given
ΔKE=KEg-KEl
⇒∆KE=500-250
⇒∆KE=250 J

Topic: Physics, Work Power Energy, NEET
An object of mass 10 kg falls from rest through a vertical distance of 10 m and acquires a velocity of 10 m s-1. The work done by the push of air on the object is g=10 m s-2

Options:
A 500 J
B â500 J
C 250Â J
D â250Â J

The correct answer is:
â500 J

Solution:
Given, the mass of the object =10 kg
Initial velocity (rest), u=0
Final velocity, v=10 m s-1
g=10 m s-2
From work-energy theorem
mgh+Wair=12mV2-12mu2
10×10×10+Wair=1210×102-0
Wair=-500 J

Topic: Physics, Work Power Energy, NEET
An object of mass 10âkg is attached to roof by string whirled round a horizontal circle of radius 4âm and inclined 30 o to the vertical. The tension in the string (approximately) is

Options:
A 720 N
B 960 N
C 114âN
D 125 N

The correct answer is:
114 N

Solution:
In figure, sin θ = AB OA
T sin θ = mv 2 r
T cos θ = mg
T = mg cos θ
T = 10 10 3 2
T = 200 3 ≈ 114 N

Topic: Physics, Laws of Motion, NEET
An object of mass 26ââkg floats in the air and it is in the equilibrium state. Air density is 1.3 kg m-3. The volume of the object is

Options:
A 10 m3
B 20 m3
C 13Â m3
D 26Â m3

The correct answer is:
20 m3

Solution:
Given, mass of object m=26 kg
Density of air Ï=1.3 kg/m3
The object is in equilibrium state.
So, mg=ÏairVg
26g=1.3Vg
V=261.3
V=20 m3

Topic: Physics, Mechanical Properties of Fluids, NEET
An object of mass 100 kg falls from point $A$ to $B$ as shown in figure. The change in its weight, corrected to the nearest integer is ( $R_E$ is the radius of the earth)

Options:
A 49 N
B 89 N
C 5 N
D 10 N

The correct answer is:
49 N

Solution:
$M g^{\prime}=M g \frac{R^2}{(R+h)^2}$
At A $\quad M g^{\prime}=M g \frac{R^2}{(R+2 R)^2}=\frac{M g}{9}$
At $B \quad M g^{\prime}=M g \frac{R}{\left(R+\frac{3 R}{2}\right)^2}=\frac{M g \cdot 4}{25}$
Change in weight $=M g \frac{4}{25}-\frac{M g}{9}=49 \mathrm{~N}$

Topic: Physics, Gravitation, NEET, NEET 2024 (Re-NEET)
An object of mass $500 \mathrm{~g}$, initially at rest acted upon by a variable force whose $\mathrm{X}$ component varies with $\mathrm{X}$ in the manner shown. The velocities of the object a point $X=8 \mathrm{~m}$ and $X=12 \mathrm{~m}$, would be the respective values of (nearly)

Options:
A $18 \mathrm{~m} / \mathrm{s}$ and $24.4 \mathrm{~m} / \mathrm{s}$
B $23 \mathrm{~m} / \mathrm{s}$ and $24.4 \mathrm{~m} / \mathrm{s}$
C $23 \mathrm{~m} / \mathrm{s}$ and $20.6 \mathrm{~m} / \mathrm{s}$
D $18 \mathrm{~m} / \mathrm{s}$ and $20.6 \mathrm{~m} / \mathrm{s}$

The correct answer is:
$23 \mathrm{~m} / \mathrm{s}$ and $20.6 \mathrm{~m} / \mathrm{s}$

Solution:
The area under the force displacement curve give the amount of work done.
From work-energy theorem,
$$
\begin{aligned}
& \mathrm{W}=\Delta \mathrm{KE} \\
& \therefore \text { At } \mathrm{x}=8 \mathrm{~m} \text {, } \\
& \mathrm{W}=\text { Area } \mathrm{ABDO}+\text { Area CEFD } \\
& =20 \times 5+10 \times 3=130 \mathrm{~J} \\
& \text { Using Eq. (i) } \\
& \Rightarrow \quad 130=\frac{1}{2} \mathrm{mv}^2=\frac{1}{2} \times \frac{500}{1000} \mathrm{v}^2 \\
& \Rightarrow \quad \mathrm{v}=2 \sqrt{130}=22.8 \mathrm{~ms}^{-1} \approx 23 \mathrm{~ms}^{-1} \\
& \text { At } \quad \mathrm{x}=12 \mathrm{~m} \\
& \mathrm{~W}=\text { Area } \mathrm{ABDO}+\text { Area CEFD + Area FGHIJ } \\
& + \text { Area KLMJ } \\
& \mathrm{W}=20 \times 5+10 \times 3+(-20 \times 2)+\left(\frac{1}{2} \times-5 \times 2\right) \\
& +10 \times 2 \quad[\because \text { Area FGHIJ }=\text { Area } \\
& \mathrm{FGIJ}+\text { Area } \mathrm{GHI}] \\
& =100+30-40-5+20=105 \mathrm{~J} \\
& \text { Using Eq. (i) } \\
& \therefore \quad 105=\frac{1}{2} \times \frac{1}{2} \times v^2 \\
& \Rightarrow \quad \mathrm{v}=2 \sqrt{105} \simeq 20.6 \mathrm{~ms}^{-1} \\
&
\end{aligned}
$$

Topic: Physics, Work Power Energy, NEET, NEET 2019 (Odisha)
An object of mass m is raised from the surface of the earth to a height equal to the radius of the earth, that is, taken from a distance R to 2R from the center of the earth. What is the gain in its potential energy?

Options:
A mgR
B mgR/2
C 2mgR
D 2mgR/3

The correct answer is:
mgR/2

Solution:
Correct Option is : (B)
mgR/2

Topic: Chemistry, Gravitation, NEET
An object will continue moving uniformly until

Options:
A the resultant force acting on it begins to decrease
B the resultant force on it is zero
C the resultant force is at right angle to its rotation
D the resultant force on it is increased continuously

The correct answer is:
the resultant force on it is zero

Solution:
From Newton's first law an object will continue to move uniformly until the resultant force on it is zero.

Topic: Physics, Laws of Motion, NEET
An observer looks at a distant tree of height 10 m with a telescope of magnifying power of 20. To the observer, the tree appears as

Options:
A 20 times taller.
B 20 times nearer.
C 10 times taller.
D 10 times nearer.

The correct answer is:
20 times nearer.

Solution:
Angular magnification of the telescope is 20 so now the tree will subtend a larger angle at the observer's eye and hence appears 20 times nearer

Topic: Physics, Ray Optics, NEET
An observer moves towards a stationary source of sound with a speed 15th of the speed of sound. The wavelength and frequency of the source emitted are λ and f respectively. The apparent frequency and wavelength recorded by the observer are respectively

Options:
A 1.2f, 1.2Î»
B 1.2f, λ
C f, 1.2λ
D 0.8f, 0.8λ

The correct answer is:
1.2f, λ

Solution:
Apparent frequency, f'=v+v0vf
⇒f'=v+1/5vvf=1.2f
Wavelength does not change by motion of observer.

Topic: Physics, Waves and Sound, NEET
An observer moves towards a stationary source of sound with a speed 1/5th of the speed of sound. The wavelength and frequency of the source emitted are $\lambda$ and $f$ respectively. The apparent frequency and wavelength recorded by the observer are respectively:

Options:
A $1.2 f, 1.2 \lambda$
B $1.2 f, \lambda$
C $f, 1.2 \lambda$
D $0.8 f, 0.8 \lambda$

The correct answer is:
$1.2 f, \lambda$

Solution:
Source is stationary
$$
\begin{aligned}
& \Rightarrow \lambda=\text { constants } \\
& \text { and } f^{\prime}=\frac{V+V_{\mathrm{s}}}{V} f=\left(1+\frac{V_{\mathrm{s}}}{V}\right) f \\
& =\left(1+\frac{1}{5}\right) f=1.2 f
\end{aligned}
$$

Topic: Physics, Waves and Sound, NEET, NEET 2003
An observer moves towards a stationary source of sound, with a velocity one-fifth of the velocity of sound. What is the percentage increase in the apparent frequency?

Options:
A 5%
B 20%
C zero
D 0.5%

The correct answer is:
20%

Solution:
fapp=f0v+v0v
fapp-f0f0=v0v=v5v=15=20%

Topic: Physics, Waves and Sound, NEET
An observer starts moving with uniform acceleration, towards a stationary sound source of frequencyf0. As the observer approaches the source, the apparent frequency(f)heard by the observer varies with time (t) is

Options:
A

B

C

D

The correct answer is:

Solution:
Let v be the speed of sound in air, vL velocity of observer at time t. As the observer approaches the source, therefore, apparent frequency
f=(v+vL)vf0=v+(0+at)vf0=f0+f0atv
This is the equation of a straight line with a positive intercept f0and positive slope f0av. Therefore, option (d) is correct.

Topic: Physics, Waves and Sound, NEET
An offset is a lateral branch with short internodes and each node bearing a rosette of leaves and a tuft of roots. It is found in:

Options:
A Pistia
B Euphorbia
C Chrysanthemum
D Zostera

The correct answer is:
Pistia

Solution:
A lateral branch with short internodes and each node bearing a rosette of leaves and a tuft of roots are found in aquatic plants like Pistia and Eichhornia.

Topic: Biology, Morphology of Flowering Plants, NEET
An oil drop carrying a charge of 2 electrons has a mass of 3.2Ã10â17 kg. It is falling freely in the air with terminal speed. The electric field required to make the drop move upwards with the same speed is

Options:
A 2 Ã 103V/m
B 4Â ÃÂ 103V/m
C 3Â ÃÂ 103V/m
D 8Â ÃÂ 103V/m

The correct answer is:
2 Ã 103V/m

Solution:
q=2e; m=3.2 Ã 10â17kg
viscous force 6ÏÎ·rv=mg (initially)â......(i)
now motion upwards
â´viscouse force downwards
6ÏÎ·rv+mg=qEâ¦â¦ii
Put value from (i) in (ii)
qE=2mg
E=2mgq=2Ã3.2Ã10-17Ã102Ã1.6Ã10-19=2 Ã 103V/m

Topic: Physics, Electrostatics, NEET
An olefinic compound on reductive ozonolysis produces formaldehyde, acetaldehyde and 1, 3-propanedial. The IUPAC name of the alkene is

Options:
A 1, 4-Hexadiene
B 2-Methyl-1, 3-pentadiene
C 1, 2-Hexadiene
D None of these

The correct answer is:
1, 4-Hexadiene

Solution:
CH 2  = CH− CH 2 −CH =  CHCH 3 → (ii)  Zn/H 2 O (i)  O 3 CH 2  = O +  CHOCH 2 CHO +  CH 3 CHO

Topic: Chemistry, Aldehydes and Ketones, NEET
An open capillary tube is lowered in a vessel with mercury. The difference between the levels of the mercury in the vessel and in the capillary tube is Îh= 4.6 mm. The radius of curvature of the mercury meniscus in the capillary tube will be (surface tension of mercury is 0.46 N m-1 of mercury is 13.6 g cm-3)

Options:
A 1340 m
B 1680 m
C 11020 m
D information is insufficient

The correct answer is:
1680 m

Solution:
Δh=2Scos⁡θrρg=2SRρg
⇒ R=2SΔhρg

Topic: Physics, Mechanical Properties of Fluids, NEET
An open glass tube is immersed in mercury in such a way that a length of 8 cm extends above the mercury level. The open end of the tube is then closed and sealed and the tube is raised vertically up by additional 46 cm . The length of the air column above the mercury, in the tube now, is (Atmospheric pressure = 76 cm of Hg)

Options:
A 38Â CM
B 6Â CM
C 16 CM
D 22 CM

The correct answer is:
16 CM

Solution:
76Ã8=54-x76-x
x=38 CM
Length of air column =54-38=16 CM

Topic: Physics, Mechanical Properties of Fluids, NEET
An optically active compound is

Options:
A 1-bromobutane
B β -bromobutyric acid
C 2-bromo-2-methylpropane
D 1-bromo-2-methylpropane

The correct answer is:
β -bromobutyric acid

Solution:
The compound B has one asymetric carbon atom; therefore, it has non-super imposable mirror-image and shows optical activity.

Topic: Chemistry, General Organic Chemistry, NEET
An optically active compound ‘X’ has molecular formula C4H8O3 . It evolves CO2 with NaHCO3. ‘X’ reacts with LiAlH4 to give an achiral compound ‘X’ is–

Options:
A
B
C
D

The correct answer is:

Solution:

Topic: Chemistry, Carboxylic Acid Derivatives, NEET
An orchid plant is growing on the branch or mango tree. Which of the following best describes the interaction between the orchid and the mango tree?

Options:
A Mutualism
B Commensalism
C Parasitism
D Camouflage

The correct answer is:
Commensalism

Solution:
An orchid plant is growing on the branch or mango tree . It shows Commensalism.

Topic: Biology, Organisms and Populations, NEET
An ore after levigation is found to have acidic impurities. Which of the following can be used as flux during smelting operation?

Options:
A H2SO4
B CaCO3
C SiO2
D Both B and C

The correct answer is:
CaCO3

Solution:
CaCO3 on heating gives CaO, which is basic in nature. It can react with acidic impurities to form slag.

Topic: Chemistry, General Principles and Processes of Isolation of Metals, NEET
An organic compound (A) contains 20% C, 46.66% N and 6.66% H. It gave NH3 gas on heating with NaOH . The organic compound (A) could be

Options:
A CH3CONH2
B C6H5CONH2
C NH2CONH2
D CH3NHCONH2

The correct answer is:
NH2CONH2

Solution:
C=2012=1.66=1
N=46.6614=3.33=2
H=6.661=6.66=4
O=26.6816=1.66=1
Empirical formula of compound CN2H4O
Since, this organic compound contains carbon, hydrogen, nitrogen and oxygen and on heating with alkali liberates NH3 the organic compound must be urea.
NH2CONH2+2NaOH→2NH3+Na2CO3

Topic: Chemistry, Some Basic Concepts of Chemistry, NEET
An organic compound (A) (molecular formula C8H16O2) was hydrolysed with dilute sulphuric acid to give a carboxylic acid (B) and an alcohol (C). Oxidation of (C) with chromic acid produced (B). (C) on dehydration gives but-1-ene. What are the structural formulas of A,B, and C?

Options:
A A=CH3CH2CH2COCH2CH3, B=CH3CH2CH2COOH, and C=CH3CH2CH2CH2OH
B A=CH3CH2CH2COOCH2CH2CH2CH3, B=CH3CH2CH2COOH, and C=CH3CH2OH
C A=CH3CH2CH2COOCH2CH2CH2CH3, B=CH3CH2COOH, and C=CH3CH2CH2CH2OH
D A=CH3CH2CH2COOCH2CH2CH2CH3, B=CH3CH2CH2COOH, and C=CH3CH2CH2CH2OH

The correct answer is:
A=CH3CH2CH2COOCH2CH2CH2CH3, B=CH3CH2CH2COOH, and C=CH3CH2CH2CH2OH

Solution:
Correct Option is : (D)
A=CH3CH2CH2COOCH2CH2CH2CH3, B=CH3CH2CH2COOH, and C=CH3CH2CH2CH2OH

Topic: Chemistry, Aldehydes and Ketones, NEET
An organic compound (A) with molecular formula C8H8O forms an orange-red precipitate with 2,4-DNP reagent and gives yellow precipitate on heating with iodine in the presence of sodium hydroxide. It neither reduces Tollens’ or Fehlings’ reagent, nor does it decolourise bromine water or Baeyer’s reagent. On drastic oxidation with chromic acid, it gives a carboxylic acid (B) having molecular formula C7H6O2. Identify the compounds (A) and (B).

Options:
A A= Acetophenone and B= Benzoic acid
B A= Acetophenone and B= Benzaldehyde
C A= Acetaldehyde and B= Benzoic acid
D A= Acetaldehyde and B= Benzaldehyde

The correct answer is:
A= Acetophenone and B= Benzoic acid

Solution:
Correct Option is : (A)
A= Acetophenone and B= Benzoic acid

Topic: Chemistry, Aldehydes and Ketones, NEET
An organic compound containing nitrogen gave an oily liquid on heating with bromine and potassium hydroxide solution. On shaking the product with acetic anhydride, an antipyretic drug was obtained. The reactions indicate that the starting compound is

Options:
A Aniline
B Benzamide
C Propanamide
D Nitrobenzene

The correct answer is:
Benzamide

Solution:
It is Hofmann Bromamide reaction given by amide, which produces amine. This should be aromatic amine which gives an antipyretic drug with acetic anhydride,
C6H5NH2+(CH3CO)2O→CH3CONHC6H5+CH3COOH

Topic: Chemistry, Amines, NEET
An organic compound containing one oxygen gives red colour with cerric ammonium nitrate solution, decolorises alkaline KMnO4 solution, responds iodoform test and shows geometrical isomerism. It should be

Options:
A C6H5-CH=CH-CH2OH
B C6H5-CH=CH-CHOHCH3
C C6H5-CH=CHCOCH3
D

The correct answer is:
C6H5-CH=CH-CHOHCH3

Solution:
(i) Compound is alcohol because it gives red colour with CAN
(ii) Compound is unsaturated as it decolorises Baeyer reagent.
(iii) Compound has group because it gives iodoform test.
Hence, this compound is C6H5-CH=CH-CHOHCH3

Topic: Chemistry, Alcohols Phenols and Ethers, NEET
An organic compound contains 69.77% carbon, 11.63% hydrogen and rest oxygen. The molecular mass of the compound is 86. It does not reduce Tollens’ reagent but forms an addition compound with sodium hydrogen sulphite and give positive iodoform test. On vigorous oxidation it gives ethanoic and propanoic acid. Write the possible structure of the compound.

Options:
A CH3COOH
B CH3COCH3
C CH3COCH2CH3
D CH3COCH2CH2CH3

The correct answer is:
CH3COCH2CH2CH3

Solution:
Correct Option is : (D)
CH3COCH2CH2CH3

Topic: Chemistry, Aldehydes and Ketones, NEET
An organic compound contains C = 40%, H=13.33% and N=46.67% . Its empirical formula is

Options:
A C2H2N
B C3H7N
C CH4N
D CHN

The correct answer is:
CH4N

Solution:
Elements	Percent by mass	Atomtextc mass	Relative number of moles of elements	Simplest molar ratio

C	40	12	4012=3.33	3.333.33= 1

H	13.33	1	13.331=13.33	13.333.33=4

N	46.67	14	46.6714=3.33	3.333.33=1

Hence, empirical ratio is CH4N .

Topic: Chemistry, Some Basic Concepts of Chemistry, NEET
An organic compound contains carbon, hydrogen and oxygen. Its elemental analysis gave $\mathrm{C}, 38.71 \%$ and $\mathrm{H}, 9.67 \%$. The empirical formula of the compound would be

Options:
A $\mathrm{CH}_3 \mathrm{O}$
B $\mathrm{CH}_2 \mathrm{O}$
C $\mathrm{CHO}$
D $\mathrm{CH}_4 \mathrm{O}$

The correct answer is:
$\mathrm{CH}_3 \mathrm{O}$

Solution:
$\text { Hence, empirical formula is } \mathrm{CH}_3 \mathrm{O} \text {. }$

Topic: Chemistry, Some Basic Concepts of Chemistry, NEET, NEET 2008 (Screening)
An organic compound contains carbon, hydrogen and oxygen. Its elemental analysis gave C, 38.71% and H, 9.67%. The empirical formula of the compound would be

Options:
A CHO
B CH4O
C CH3O
D CH2O

The correct answer is:
CH3O

Solution:
Element	%	Atomic mass	mole ratio	simple ratio

C	38.71	12	38.7112=3.22	3.223.22=1

H	9.67	1	9.671=9.67	9.673.22=3

O	51.62	16	51.6216=3.22	3.223.22=1

Hence empirical formula of the compound would be CH3O .

Topic: Chemistry, General Organic Chemistry, NEET
An organic compound having elements with composition C = 40%, H = 6.7% and O = 53.3%. What will be the empirical formula of the compound?

Options:
A C2H4O2
B CH2O
C C3H6O3
D CH2

The correct answer is:
CH2O

Solution:
Elements	No. of moles	Simple ratio

C = 40%	40/12	3.33	1

H = 6.7%	6.7/1	6.7	2

O = 53.3%	5.33/16	3.33	1

Thus, Empirical formula = CH2O .

Topic: Chemistry, General Organic Chemistry, NEET
An organic compound having molecular mass 60 u is found to contain C = 20%, H = 6.67% and N = 46.67% rest being oxygen. On heating, it gives NH 3 along with solid residue. The solid residue gives violet colour with alkaline copper sulphate solution. The compound is

Options:
A CH 3 NCO
B CH 3 CONH 2
C (NH 2 ) 2 CO
D CH 3 CH 2 CONH 2

The correct answer is:
(NH 2 ) 2 CO

Solution:
The given data of empirical formula give, the formula of the compound as N 2 H 4 CO. The sequence of reactions supports this compound to be urea.

Biuret gives violet colour with alkaline copper sulphate solution.

Topic: Chemistry, General Organic Chemistry, NEET
An organic compound of molecular formula, C3H6O, forms 2, 4-dinitrophenylhydrazone, but gives negative Tollen's test. The compound is

Options:
A CH2=CH-CH2-OH
B CH3CH2CHO
C CH3COCH3
D CH2=CH-OCH3

The correct answer is:
CH3COCH3

Solution:
An organic compound of molecular formula, C3H6O, forms 2, 4-dinitrophenylhydrazone, but gives negative Tollen's test. The compound is CH3COCH3

Topic: Chemistry, Aldehydes and Ketones, NEET
An organic compound (P) upon reacting with NH3 gives (Q). On heating, (Q) gives (R). (R) in presence of KOH reacts with Br2 to give ethylamine. (P) is

Options:
A
B CH3CH2COOH
C CH3COOH
D CH3CH2CH2COOH

The correct answer is:
CH3CH2COOH

Solution:
CH 3 CH 2 COOH P  +  NH 3 → CH 3 CH 2 C O ¯ 2 N + H 4 Q → − H 2 O Δ CH 3 CH 2 CO +  NH 2 R → KOH +  Br 2 CH 3 CH 2 NH 2 +H 2 O

Topic: Chemistry, Carboxylic Acid Derivatives, NEET
An organic compound undergoes first order decomposition. The time taken for its decomposition to 1/8 and 1/10 of its initial concentration are t1/8 and t1/10 respectively.
What is the value of [t1/8]t1/10 ?
(take log102=0.3 )

Options:
A 0.6
B 3
C 0.9
D 9

The correct answer is:
0.9

Solution:
As we know
kt=lnA0At
t1/8t1/10=ln8ln10=0.9
t1/8t1/10=0.9

Topic: Chemistry, Chemical Kinetics, NEET
An organic compound with the molecular formula C9H10O forms 2,4-DNP derivative, reduces Tollens’ reagent and undergoes Cannizzaro reaction. On vigorous oxidation, it gives 1,2-benzenedicarboxylic acid. Identify the compound.

Options:
A 2-Ethylbenzaldehyde
B 2-Methylbenzaldehyde
C 2-Ethylbenzoic acid
D 3-Ethylbenzaldehyde

The correct answer is:
2-Ethylbenzaldehyde

Solution:
Correct Option is : (A)
2-Ethylbenzaldehyde

Topic: Chemistry, Aldehydes and Ketones, NEET
An organic compound (X), C7H8O , is insoluble in both NaHCO3 and NaOH. On treatment with bromine-water (X) rapidly forms compound of molecular formula, C7H5OBr3 . The compound (X) is

Options:
A o-cresol
B p-cresol
C m-cresol
D anisole

The correct answer is:
anisole

Solution:
Insolubility in NaOH and NaHCO3 indicates the compound can neither be a phenol nor carboxylic acid. It may be anisole,

Topic: Chemistry, Alcohols Phenols and Ethers, NEET
An organic compound 'X' having molecular formula C5H10O yields phenyl hydrazone and gives negative response to the iodoform test and Tollen's test. It produces n-pentane on reduction. 'X' could be:

Options:
A Pentanal
B 2-Pentanone
C 3-Pentanone
D n-Amyl alcohol

The correct answer is:
3-Pentanone

Solution:
The above ketone does not give Tollen's test & iodo form test as it does not have aldehyde or ketonic group.

Topic: Chemistry, Aldehydes and Ketones, NEET, NEET 2015 (Phase 1)
An organic compound 'X' having molecular formula C5H10O yields phenyl hydrazone and gives negative response to the Iodoform test and Tollen's test. It produces n-pentane on reduction. 'X' could be

Options:
A pentanal
B 3-pentanone
C 2-pentanone
D n-amyl alcohol

The correct answer is:
3-pentanone

Solution:
According to questions CH3-CH2-C||O-CH2-CH3 does not give iodoform as well as Tollen’s test

Topic: Chemistry, Aldehydes and Ketones, NEET
An organic compound (X) of the formula C7H8O is soluble in NaOH but not in NaHCO3 . It gives colour with alcoholic FeCl3 . On treatment with bromine water it gives tribromo product. The compound 'A' is

Options:
A o-cresol
B m-cresol
C p-cresol
D either of the three

The correct answer is:
m-cresol

Solution:
Compound is soluble in NaOH but insoluble in NaHCO3 hence compound is phenolic in nature.
Only m-derivative will give tribromo derivative.

Topic: Chemistry, Alcohols Phenols and Ethers, NEET
An organic molecule necessarily shows optical activity if it –

Options:
A Contains asymmetric carbon atoms
B Is non-planar
C Is non-superimposable on its mirror image
D Is superimposable on its mirror image

The correct answer is:
Is non-superimposable on its mirror image

Solution:
Asymmetric molecule is optically active. These molecules are non-superimposable on their mirror image.

Topic: Chemistry, General Organic Chemistry, NEET
An organic substance bound to an enzyme and essential for its activity is called:

Options:
A isoenzyme
B coenzyme
C holoenzyme
D apoenzyme.

The correct answer is:
coenzyme

Solution:
Coenzyme is an organic non-protein molecule that associates with an enzyme molecule in catalysing biochemical reactions. It usually participates in the substrate-enzyme interaction by donating or accepting certain chemical groups. Holoenzyme is a complex comprising of enzyme molecule and its cofactor. The enzyme is catalytically active in this state. Apoenzyme is an inactive enzyme that must associate with a specific cofactor molecule in order to function. Isoenzyme or isozyme is one of the several forms of an enzyme that catalyse the same reaction but differ from each other in such properties as substrate affinity and maximum rates of enzymesubstrate reaction.

Topic: Biology, Biomolecules (B), NEET, NEET 2006
An organic substance that can withstand environmental extremes and cannot be degraded by any enzyme is

Options:
A cuticle
B sporopollenin
C lignin
D cellulose

The correct answer is:
sporopollenin

Solution:
Sporopollenin is a fatty substance present in the exine of pollen grains. It is resistant to microbial and chemical decomposition and can withstand the extreme environmental conditions. Due to presence of sporopollenin, pollen grains are well preserved during fossilization.

Topic: Biology, Sexual Reproduction in Flowering Plants, NEET, NEET 2012 (Screening)
An organic substance that can withstand environmental extremes and cannot be degraded by any enzyme is :

Options:
A Cuticle
B Sporopollenin
C Lignin
D Cellulose

The correct answer is:
Sporopollenin

Solution:
Sporopollenin is a fatty substance present in the pollen wall and provides resistance against extremes conditions like high temperature, acid, bases.

Topic: Biology, Sexual Reproduction in Flowering Plants, NEET