datavorous/entrance-exam-dataset huggingface dataset:
Which one of the following is a matching set of the class and some of its main distinguishing features, classification, and examples?

Options:
A Cyclostomata - Division Agnatha; 6-15 pairs of gill slits, endoskeleton bony, Example: Myxine
B Reptilia - Division Gnathostomata; epidermal scutes, endoskeleton body, Example: Hemidactylus
C Amphibia - Super-class Tetrapoda, cloaca as a common opening for the alimentary canal, urinary tract and reproductive tract, exoskeleton bony, Example: Hyla
D Chondrichthyes - Super-class Pisces; gill slits without operculum, exoskeleton cartilaginous, Example: Carcharodon

The correct answer is:
Reptilia - Division Gnathostomata; epidermal scutes, endoskeleton body, Example: Hemidactylus

Solution:
Reptiles are classified under division Gnathostomata and superclass Tetrapoda. The class name Reptilia refers to their creeping or crawling mode of locomotion (Latin, repere or reptum, to creep or crawl). They are mostly terrestrial animals and their body is covered by dry and cornified skin, epidermal scales, or scutes. They do not have external ear openings. Tympanum represents ear. Limbs, when present, are two pairs. The heart is usually three-chambered, but four-chambered in crocodiles. Reptiles are poikilotherms. Snakes and lizards shed their scales as skin cast. Sexes are separate. Fertilization is internal. They are oviparous and development is direct.
Examples: Chelone (Turtle), Testudo (Tortoise), Chameleon (Tree lizard), Calotes (Garden lizard), Crocodilus (Crocodile), Alligator (Alligator). Hemidactylus (Wall lizard), Poisonous snakes â Naja (Cobra), Bangarus (Krait), Vipera (Viper).

Topic: Biology, Animal Kingdom, NEET
Which one of the following is a possibility for most of us in regard to breathing, by making a conscious effort?

Options:
A One can breathe out air totally without oxygen
B One can breathe out air through eustachian tubes by closing both the nose and the mouth
C One can consiously breathe in and breathe out by moving the diaphragm alone, without moving the ribs at all
D The lungs can be made fully empty by forcefully breathing out all air from them

The correct answer is:
One can consiously breathe in and breathe out by moving the diaphragm alone, without moving the ribs at all

Solution:
The process of breathing involves the pathway of the human respiratory system and includes the nasal cavities, oral cavities, pharynx, trachea, primary bronchi, secondary bronchi and lungs with bronchioles and alveoli present. Breathing is a 2-fold process which includes breathing in and breathing out. During this process, the diaphragm which is the dome-shaped sheet of muscle located below the lungs contracts and expands along with the intercostal muscles to force air in and out of the lungs. Since intercostal muscles are also involved in the process of respiration, deeper respiration results in the movement of ribs too. Hence most of us can consciously breathe in and breathe out by moving the diaphragm alone.

Topic: Biology, Breathing and Exchange of Gases, NEET, NEET 2011 (Mains)
Which one of the following is a tautology?

Options:
A p∧p→q→q
B q→p∧p→q
C p∧p∨q
D p∨p∧q

The correct answer is:
p∧p→q→q

Solution:
p	q	p→q	p∧p∧→q	p∧p→q→q	q→p∧p→q	p∧q	p∨p∧q	p∨q	p∧p∨q

T	T	T	T	T	T	T	T	T	T

T	F	F	F	T	T	F	T	T	T

F	T	T	F	T	F	F	F	T	F

F	F	T	F	T	T	F	F	F	F

Topic: Mathematics, Mathematical Reasoning, JEE Main, JEE Main 2020 (08 Jan Shift 1)
Which one of the following is a true peroxide

Options:
A $\mathrm{SO}_2$
B $\mathrm{BaO}_2$
C $\mathrm{MnO}_2$
D $\mathrm{NO}_2$

The correct answer is:
$\mathrm{BaO}_2$

Solution:
Barium peroxide $\mathrm{BaO} 2$ is a true peroxide. It contains peroxide ion, $\mathrm{O} 2-2$ ion. It is a white ionic solid obtained by the reaction of barium hydroxide with hydrogen peroxide.

Topic: Chemistry, s Block Elements, JEE Main
Which one of the following is a vascular cryptogram ?

Options:
A Cedrus
B Equisetum
C Ginkgo
D Marchantia

The correct answer is:
Equisetum

Solution:
No Solution Available

Topic: Biology, Plant Kingdom, NEET, NEET 2009 (Mains)
Which one of the following is a water soluble vitamin, that is not excreted easily?

Options:
A Vitamin B2
B Vitamin B1
C Vitamin B6
D Vitamin B12

The correct answer is:
Vitamin B12

Solution:
B group vitamins and vitamin C are soluble in water, so they are grouped together. Water-soluble vitamins must be supplied regularly in diet because they are readily excreted in urine and cannot be stored (except vitamin B12) in our body.

Means vitamin B12can not be excreted easily.

Topic: Chemistry, Biomolecules, JEE Main, JEE Main 2022 (26 Jun Shift 2)
Which one of the following is a wrong matching of a microbe and its industrial product, while the remaining three are correct?

Options:
A Yeast - statins
B Acetobacter aceti - acid
C Clostridium butulicum - lactic acid
D Aspergillus niger - citric acid

The correct answer is:
Clostridium butulicum - lactic acid

Solution:
Clostridium butulicum forms butyric acid.

Topic: Biology, Microbes in Human Welfare, NEET, NEET 2011 (Mains)
Which one of the following is a WRONG statement?

Options:
A Ozone in the upper part of the atmosphere is harmful to animals.
B The greenhouse effect is a natural phenomenon.
C Eutrophication is a natural phenomenon in freshwater bodies.
D Most of the forests have been lost in tropical areas.

The correct answer is:
Ozone in the upper part of the atmosphere is harmful to animals.

Solution:
Depletion of forest trees on a large scale is referred to as deforestation and is the main cause of extinction of species from tropical areas. Deforestation has led to increase in human and livestock population which puts a stress on the limited to resources available in the environment.
Ozone in the stratosphere is considered good ozone as it helps in limiting the entry of UV-rays to Earth surface and protecting us from skin-burn and skin cancer due to over-exposure.
Ozone found in the troposphere is considered as bad ozone cause this ozone increases the smog formation and density hampering vision. Also, ozone if inhaled leads to breathing and other respiratory problems.
Natural aging and nutrient enrichment of a water body is termed as eutrophication. Due to the human activities of adding sewage and industrial waste, water bodies like lake have been heavily eutrophised. Contaminants like nitrates and phosphates overstimulate algal growth as a consequence deplete the oxygen level in water body. Also, other pollutants poison the population of aquatic life leading to their death and increasing the rate of decomposition by bacteria which further depletes the oxygen level. As a result, the aquatic life in water body chokes to death.
The greenhouse effect is a natural phenomenon keeping the atmosphere warm enough for life to occur on the planet and sustain. This is due to absorption of part of the heat energy, while the remainder escapes into space. Water vapor, carbon dioxide, methane and nitrous oxide are part of the greenhouse gases in the atmosphere.

Topic: Biology, Environmental Issues, NEET
Which one of the following is a wrong statement regarding mutations?

Options:
A Deletion and insertion of base pairs cause frame-shift mutations
B Cancer cells commonly show chromosomal aberrations
C UV and gamma rays are mutagens
D Change in a single base pair of DNA does not cause mutaiton

The correct answer is:
Change in a single base pair of DNA does not cause mutaiton

Solution:
Change in single base pair of DNA cause mutation as if it mutated to termination codon or other amino acid codon specific. Cancer is the uncontrolled process of cell division. The causal agents are certain chemicals, radiation, viruses that behave as mutagen by acting at DNA. It is believed that cancer is a genetic disease caused by multiple mutation within the DNA.

Topic: Biology, Principles of Inheritance and Variation, NEET, NEET 2012 (Mains)
Which one of the following is a xerophytic plant in which the stem is modified into the flat green and succulent structure?

Options:
A Opuntia
B Casuarina
C Hydrilla
D Acacia

The correct answer is:
Opuntia

Solution:
Opuntia is a plant growing in dry and xeric habitats. In this, the stem having several nodes and internodes is modified into flat, fleshy, thick, green leaf-like structure called phylloclade. Phylloclade performs the function of photosynthesis like a leaf and also stores food. The leaves get modified into spines which helps to reduce transpiration.

Topic: Biology, Morphology of Flowering Plants, NEET, NEET 2010 (Mains)
Which one of the following is an amine hormone?

Options:
A Progesterone
B Thyroxine
C Oxypurin
D Insulin

The correct answer is:
Thyroxine

Solution:
Thyroxine-derived from tyrosine amino acid.
Insulin - Polypeptide.
Progesterone - Steroid hormone.

Topic: Chemistry, Biomolecules, NEET, NEET 2008 (Mains)
Which one of the following is an amino acid

Options:
A $\mathrm{CH}_3 \mathrm{CONH}_2$
B $\mathrm{CH}_3 \mathrm{CONHCH}_3$
C $\mathrm{CH}_3 \mathrm{NHCHO}$
D $\mathrm{NH}_2 \mathrm{CH}_2 \cdot \mathrm{COOH}$

The correct answer is:
$\mathrm{NH}_2 \mathrm{CH}_2 \cdot \mathrm{COOH}$

Solution:
Glycine $\rightarrow \mathrm{NH}_2-\mathrm{CH}_2-\mathrm{COOH}$

Topic: Chemistry, Biomolecules, JEE Main
Which one of the following is an amphoteric oxide?

Options:
A
$\mathrm{Na}_2 \mathrm{O}$

B
$\mathrm{SO}_2$

C
$\mathrm{B}_2 \mathrm{O}_3$

D
$\mathrm{ZnO}$

The correct answer is:
$\mathrm{ZnO}$

Solution:
No Solution Available

Topic: Chemistry, d and f Block Elements, JEE Main, JEE Main 2003
Which one of the following is an environmentrelated disorder with the correct main cause ?

Options:
A Black lung disease (pneumoconiosis) found mainly in workers in stone quarries and crushers.
B Blue baby disease (methaemoglobinaemia) due to heavy use of nitrogenous fertilizers in the area.
C Non-hodgkin's lymphoma found mainly in workers involved in manufacture of neem based pesticides.
D Skin cancer mainly in people exposed to benzene and methane.

The correct answer is:
Blue baby disease (methaemoglobinaemia) due to heavy use of nitrogenous fertilizers in the area.

Solution:
Blue baby syndrome is a pathological condition, called methemoglobinemia, in which blood's capacity for oxygen transport is reduced, resulting in bluish skin discoloration in infants. Blue baby syndrome begins when large amounts of nitrates in water are ingested by an infant and converted to nitrite by the digestive system. The nitrite then reacts with oxyhaemoglobin (the oxygen-carrying blood protein) to form metheglobin, which cannot carry oxygen.
Pneumoconiosis is a man-made, occupational lung diseases that are contracted by prolonged breathing of coal mine dust i.e. caused by the inhalation of dust, characterized by formation of nodular fibrotic changes in lungs.
Non-Hodgkin lymphoma (or NHL) is a cancer of lymphoid tissue, a part of the lymphatic system. NHL is a heterogenous disease.
Skin cancer is a malignant tumor that grows in the skin cells. It is commonly caused by exposure to the sun's UV rays.

Topic: Biology, Human Reproduction, AIIMS, AIIMS 2006
Which one of the following is an example of disproportionation reaction?

Options:
A $\begin{aligned} & 3 \mathrm{Cl}_2(g)+6 \mathrm{OH}^{-}(a q) \longrightarrow \mathrm{ClO}_3^{-}(a q)+5 \mathrm{Cl}^{-}(a q) \\ & +3 \mathrm{H}_2 \mathrm{O}(l) \\ & \end{aligned}$
B $\mathrm{Ag}^{2+}(\mathrm{aq})+\mathrm{Ag}(\mathrm{s}) \longrightarrow 2 \mathrm{Ag}^{+}(\mathrm{aq})$
C $\mathrm{Zn}(s)+\mathrm{CuSO}_4(a q) \longrightarrow \mathrm{Cu}(s)+\mathrm{ZnSO}_4(a q)$
D $2 \mathrm{KClO}_3(\mathrm{~s}) \longrightarrow 2 \mathrm{KCl}(\mathrm{s})+3 \mathrm{O}_2(\mathrm{~g})$

The correct answer is:
$\begin{aligned} & 3 \mathrm{Cl}_2(g)+6 \mathrm{OH}^{-}(a q) \longrightarrow \mathrm{ClO}_3^{-}(a q)+5 \mathrm{Cl}^{-}(a q) \\ & +3 \mathrm{H}_2 \mathrm{O}(l) \\ & \end{aligned}$

Solution:
A reaction in which the same species is simultaneously oxidised as well as reduced is called a disproportionation reaction.

Topic: Chemistry, Redox Reactions, JEE Main
Which one of the following is an example of disproportionation reaction?

Options:
A 3MnO42-+4H+→2MnO4-+MnO2+2H2O
B MnO4-+4H++4e-→MnO2+2H2O
C 10I-+2MnO4-+16H+→2Mn2++8H2O+5I2
D 8MnO4-+3 S2O32-+H2O→8MnO2+6SO42-+2OH-

The correct answer is:
3MnO42-+4H+→2MnO4-+MnO2+2H2O

Solution:
Disproportionation reaction, also sometimes called dismutation reaction, is basically a type of redox reaction involving simultaneous reduction and oxidation of atoms of the same element from one oxidation state (OS) to two different oxidation states.

3MnO42-+6+4H+⟶2MnO4-+7+MnO2+4+2H2O

Topic: Chemistry, Redox Reactions, JEE Main, JEE Main 2022 (26 Jun Shift 2)
Which one of the following is an example of ex-situ conservation?

Options:
A Wildlife sanctuary
B Seed bank
C Sacred groves
D National park

The correct answer is:
Seed bank

Solution:
Ex situ conservation means conservation outside the habitats by perpetuating sample population in genetic resource centres or in the form of gene pool. This form of conservation includes zoos, botanical gardens, seed banks, pollen storage, tissue culture, genetic engineering.
In situ is the conservation of living resources through their maintenance within the natural ecosystems, in which, they occur. In situ conservation includes a comprehensive system of protected areas such as the National parks, sanctuaries, natural reserves, biosphere reserves and several others.

Topic: Biology, Biodiversity and its Conservation, NEET, NEET 2010 (Screening)
Which one of the following is an example of homogeneous catalysis?

Options:
A manufacture of ammonia by Haber's process
B manufacture of sulphuric acid by contact process
C hydrogenation of oil
D Hydrolysis of sucrose in presence of dil \( \mathrm{HCl} \)

The correct answer is:
Hydrolysis of sucrose in presence of dil \( \mathrm{HCl} \)

Solution:
In a homogeneous catalysed reaction, the reactants, products and catalyst are present in the same phase. Hydrolysis of cane sugar with a mineral acid as a catalyst is an example of homogeneous catalysis in which the reactants, products and catalyst are present in aqueous solution.

C12H12O11aq + H2Ol →HCldil. C6H12O6aq + C6H12O6aq

Topic: Chemistry, Surface Chemistry, JEE Main
Which one of the following is an example of thermosetting polymer?

Options:
A Nylon -6,6
B Bakelite
C Buna - N
D Teflon

The correct answer is:
Bakelite

Solution:
Thermosetting polymer :A thermosetting polymer can be moulded into desired shape when hot, but once these get cooled and hardened, they cannot be remoulded again. An example of this is Bakelite.

Topic: Chemistry, Polymers, JEE Main, JEE Main 2014 (19 Apr Online)
Which one of the following is an ingredient of Pthalic acid manufacture by catalytic oxidation

Options:
A Benzene
B Salicylic acid
C Anthranilic acid
D naphthalene

The correct answer is:
naphthalene

Solution:

Topic: Chemistry, Carboxylic Acid Derivatives, JEE Main
Which one of the following is an inner orbital complex as well as diamagnetic in behaviour?
(Atomic number : $\mathrm{Zn}=30, \mathrm{Cr}=24$, $\mathrm{Co}$ $=27, \mathrm{Ni}=28$ )

Options:
A $\left[\mathrm{Zn}\left(\mathrm{NH}_3\right)_6\right]^{2+}$
B $\left[\mathrm{Cr}\left(\mathrm{NH}_3\right)_6\right]^{3+}$
C $\left[\mathrm{Co}\left(\mathrm{NH}_3\right)_6\right]^{3+}$
D $\left[\mathrm{Ni}\left(\mathrm{NH}_3\right)_6\right]^{2+}$

The correct answer is:
$\left[\mathrm{Co}\left(\mathrm{NH}_3\right)_6\right]^{3+}$

Solution:
$d^2 s p^3 \rightarrow$ inner octahedral complex $\&$ diamagnetic.
$$
\left[\mathrm{Zn}\left(\mathrm{NH}_3\right)_6\right]^{2+} \longrightarrow s p^2 d^2
$$
hybridization (outer) and diamagnetic.
$\left[\mathrm{Cr}\left(\mathrm{NH}_3\right)_6\right]^{3+} \longrightarrow d^2 s p^3$ (inner) and
paramagnetic.
$\left[\mathrm{Ni}\left(\mathrm{NH}_3\right)_6\right]^{3+} \longrightarrow s p^3 p^2$ (outer) and
paramagnetic.
Related Theory
The main difference between inner and outer orbital complexes is that the hybridization of the atomic orbitals of the central metal atom of inner orbital complex involves inner shell $d$ orbitals whereas the hybridization of the atomic orbitals of the central metal atom of outer orbital complex involves outermost shell d orbitals.

Topic: Chemistry, Coordination Compounds, NEET, NEET 2005
Which one of the following is an optically active compound

Options:
A n-propanol
B 2-chlorobutane
C n-butanol
D 4-hydroxyheptane

The correct answer is:
2-chlorobutane

Solution:

Topic: Chemistry, General Organic Chemistry, JEE Main
Which one of the following is an oxide?

Options:
A SiO2
B KO2
C BaO2
D CsO2

The correct answer is:
SiO2

Solution:
SiO2 is a 3D polymer of tetrahedral SiO4-4 units.

S i 4+ +  O 2− →oxide
K + + O 2 − →  superoxide
B a 2+ + O 2 2− →peroxide
C s + + O 2 − → superoxide

Topic: Chemistry, p Block Elements (Group 13 & 14), JEE Main, JEE Main 2017 (09 Apr Online)
Which one of the following is being tried in India as a biofuel substitute for fossil fuels?

Options:
A Aegilops
B Jatropha
C Azadirachta
D Musa

The correct answer is:
Jatropha

Solution:
It is a petroplant and the source of fuel is latex.

Topic: Biology, Strategies for Enhancement in Food Production, NEET, NEET 2008 (Mains)
Which one of the following is categorised under living fossils?

Options:
A Pinus
B Cycas
C Selaginella
D Metasequoia

The correct answer is:
Cycas

Solution:
Cycas is called a Living Fossil because, Cycads are one of the oldest forms of plant life; they were here long, long before dinosaurs stomped the Earth and have remained basically unaffected.

Topic: Biology, Plant Kingdom, NEET, NEET 2003
Which one of the following is commonly used in transfer of foreign DNA into crop plants ?

Options:
A Penicillium expansum
B Trichoderma harzianum
C Meloidogyne incognita
D Agrobacterium tumefaciens

The correct answer is:
Agrobacterium tumefaciens

Solution:
No Solution Available

Topic: Biology, Biotechnology - Principles and Processes, NEET, NEET 2009 (Mains)
Which one of the following is considered as the main postulate of Bohr's model of atom.

Options:
A Protons are present in the nucleus
B Electrons are revolving around the nucleus
C Centrifugal force produced due to the revolving electrons balances the force of attraction between the electron and the protons
D (d) Angular momentum of electron is an integral multiple of $\frac{h}{2 \pi}$

The correct answer is:
(d) Angular momentum of electron is an integral multiple of $\frac{h}{2 \pi}$

Solution:
The electron can move only in these circular orbits where the angular momentum is a whole number multiple of $\frac{h}{2 \pi}$ or it is quantised.

Topic: Chemistry, Structure of Atom, JEE Main
Which one of the following is considered important in the development of seed habit ?

Options:
A Free-living gametophyte
B Dependent sporophyte
C Heterospory
D Haplontic life cycle

The correct answer is:
Heterospory

Solution:
No Solution Available

Topic: Biology, Plant Kingdom, NEET, NEET 2009 (Mains)
Which one of the following is correct

Options:
A Skew-symmetric matrix of odd order is non-singular
B Skew-symmetric matrix of odd order is singular
C Skew-symmetric matrix of even order is always singular
D None of these

The correct answer is:
Skew-symmetric matrix of odd order is singular

Solution:
A skew-symmetric matrix \(A\) is defined such that \(A^T=-A\). One important property of skewsymmetric matrices is that all the diagonal elements must be zero.
Skew-Symmetric Matrix of Odd Order
Consider a skew-symmetric matrix of odd order \(n\). One key property is that the determinant of a skew-symmetric matrix of odd order is always zero. This implies that the matrix is singular (it does not have an inverse).

Topic: Mathematics, Matrices, JEE Main
Which one of the following is correct?

Options:
A $\mathrm{RCH}_{2} \mathrm{OH} \quad \stackrel{\mathrm{KMnO}_{4}}{\longrightarrow}$ No reaction
B
C
D

The correct answer is:

Solution:
$3^{\circ}$ alcohols are resistant to oxidation and are oxidised only by strong oxidising agents like conc. $\mathrm{HNO}_{3}$. They are resistant to oxidation in neutral or alkaline $\mathrm{KMnO}_{4}$.

Topic: Chemistry, Alcohols Phenols and Ethers, JEE Main
Which one of the following is correct in respect of the function
$f(x)=x \sin x+\cos x+\frac{1}{2} \cos ^{2} x ?$

Options:
A It is increasing in the interval $\left(0, \frac{\pi}{2}\right)$
B It remain constant in the interval $\left(0, \frac{\pi}{2}\right)$
C It is decreasing in the interval $\left(0, \frac{\pi}{2}\right)$
D It is decreasing in the interval $\left(\frac{\pi}{4}, \frac{\pi}{2}\right)$

The correct answer is:
It is increasing in the interval $\left(0, \frac{\pi}{2}\right)$

Solution:
$f(x)=x \sin x+\cos x+\frac{1}{2} \cos ^{2} x$
$\Rightarrow \quad f^{\prime}(x)=x \cos x+\sin x-\sin x-\sin x \cos x$
$=\cos x(x-\sin x)>0$ in $\left(0, \frac{\pi}{2}\right)$

Topic: Mathematics, Application of Derivatives, NDA, NDA 2018 (Phase 2)
Which one of the following is correct in respect of the
function $f(x)=|x|+x^{2}$

Options:
A $f(x)$ is not continuous at $x=0$
B $f(x)$ is differentiable at $x=0$
C $f(x)$ is continuous but not differentiable at $x=0$
D None of the above

The correct answer is:
$f(x)$ is continuous but not differentiable at $x=0$

Solution:
$\because \quad f(x)=|x|+x^{2}$
$\Rightarrow f(x)=\left\{\begin{array}{ll}x^{2}+x, & x \geq 0 \\ x^{2}-x, & x < 0\end{array}\right.$
LHL $=\lim _{x \rightarrow 0^{-}} f(x)$
$=\lim _{h \rightarrow 0} f(0-h)=\lim _{h \rightarrow 0}(0-h)^{2}-(0-h)$
$=\lim _{h \rightarrow 0} h^{2}+h=0$
and $\operatorname{RHL}=\lim _{x \rightarrow 0} f(x)=\lim _{h \rightarrow 0} f(0+h)$
$=\lim _{h \rightarrow 0}(0+h)^{2}+(0+h)=\lim _{h \rightarrow 0} h^{2}+h=0$
$\Rightarrow \mathrm{LHL}=\mathrm{RHL}=\mathrm{f}(0)$
$\Rightarrow f(x)$ is continuous at $x=0$
Now, $\mathrm{LHD}=\lim _{h \rightarrow 0} \frac{f(0-h)-f(0)}{-h}$
$=\lim _{h \rightarrow 0} \frac{h^{2}+h}{-h}=-\lim _{h \rightarrow 0} h+1=-1$
and, $\mathrm{RHD}=\lim _{h \rightarrow 0} \frac{f(0+h)-f(0)}{h}$
$=\lim _{h \rightarrow 0} \frac{h^{2}+h}{h}=\lim _{h \rightarrow 0} h+1=1$
Thus, $\mathrm{LHD} \neq \mathrm{RHD}$
$\Rightarrow f(x)$ is not differentiable at $x=0$

Topic: Mathematics, Continuity and Differentiability, JEE Main
Which one of the following is correct pairing of a body part and like kind of muscle tissue that moves it?

Options:
A Iris - Involuntary smooth muscle
B Heart wall - Involuntary unstriated muscle
C Biceps of upper arm - smooth muscle fibres
D Abdominal wall - smooth muscle

The correct answer is:
Iris - Involuntary smooth muscle

Solution:
No Solution Available

Topic: Biology, Structural Organisation in Animals, NEET, NEET 2009 (Mains)
Which one of the following is correct plot of $\Lambda_{\mathrm{m}}\left(\right.$ in $\mathrm{scm}^2 \mathrm{~mol}^{-1}$ ) and $\sqrt{C}$ (in $\mathrm{mol} / \mathrm{L}^{1 / 2}$ ) for KCl solution? $\left(y=\Lambda_m ; x-\sqrt{C}\right)$

Options:
A

B

C

D

The correct answer is:

Solution:
Molar conductivity is given as $\Lambda_m=\Lambda_m^{\circ}-A \sqrt{C}$ Thus, as the $\sqrt{C}$ increases , $\Lambda_m$ decreases.

Topic: Chemistry, Electrochemistry, JEE Main
Which one of the following is correct regarding $\Delta \mathrm{H}:$

Options:
A $\quad \Delta \mathrm{H}=\Delta \mathrm{E}+2 \mathrm{RT}$
B $\quad \Delta \mathrm{H}=\Delta \mathrm{E}-2 \mathrm{RT}$
C $\Delta \mathrm{H}=\Delta \mathrm{E}+\mathrm{RT}$
D $\quad \Delta \mathrm{H}=\Delta \mathrm{E}-\mathrm{RT}$

The correct answer is:
$\quad \Delta \mathrm{H}=\Delta \mathrm{E}-2 \mathrm{RT}$

Solution:
$\mathrm{N}_{2}+3 \mathrm{H}_{2} \rightleftharpoons 2 \mathrm{NH}_{3}$
According to thermodynamics's Ist law
$$
\Delta \mathrm{H}=\Delta \mathrm{E}+\mathrm{nRT}
$$
Where $\Delta \mathrm{H}=$ enthalpy of reaction at constant pressure $\Delta \mathrm{E}=$ heat of reaction at constant volume $\mathrm{R}=$ molar gas constant
$$
\begin{array}{l}
\mathrm{T}=\text { temperature of the reaction } \\
\mathrm{n}=(\text { no. of moles of product })-(\text { no. of moles }
\end{array}
$$
of reactant.) From reaction, $\mathrm{n}=\mathrm{n}_{\mathrm{p}}-\mathrm{n}_{\mathrm{R}}=2-4=-2$
Hence, $\Delta \mathrm{H}=\Delta \mathrm{E}-2 \mathrm{RT}$.

Topic: Chemistry, Thermodynamics (C), JEE Main