AIEEE Chemistry - Physical, Organic & Biochemistry

The Arrhenius equation K = A e^(-Ea/RT) correctly relates the rate constant K to temperature T, where A is the pre-exponential factor, Ea is activation energy, and R is the gas constant. Option A has incorrect exponent form, B lacks the pre-exponential factor, and D has positive exponent instead of negative.

Adsorption is a surface phenomenon where molecules adhere to the surface of solids or liquids. Absorption involves bulk penetration throughout the material. Catalysis is a process of increasing reaction rate, and induction refers to electromagnetic phenomena.

Tyndall effect is the scattering of light by colloidal particles, making the path of light visible through a colloid. It is not due to pressure, absorption (which would diminish light intensity), or reflection.

Colloidal medicines have larger surface area and are easily absorbed and assimilated by biological membranes due to their particle size. Options A and B are not primary reasons, and option C has grammatical issues and lacks scientific precision.

Using pH = -log[H+], when pH = 2, [H+] = 10^(-2) = 1 × 10^(-2) moles per litre. Option A would give pH 12, option C gives pH 7 (neutral), and option D gives pH 4.

2-pentanone (CH3CO(CH2)2CH3) gives a positive iodoform test because it contains the CH3CO- group (methyl ketone). 1-pentanol lacks a carbonyl, 3-pentanone has no methyl group attached to carbonyl, and pentanal is an aldehyde.

Phenolphthalein turns pink in alkaline (basic) medium. In acidic medium it remains colorless. Red and yellow are not the correct colors for phenolphthalein in basic conditions.

Atomic radii increase down a group: I (iodine) > Br (bromine) > Cl (chlorine). Hydrogen has the smallest atomic radius among all elements. Options A and C have incorrect ordering, and D shows decreasing trend.

Glycerol is used as a sweetening agent in food, in soap manufacturing to improve quality, and in nitroglycerin production. The 'All of the above' option correctly encompasses all these uses.

For first-order reaction, k = 0.693/t(1/2) = 0.693/10 = 0.0693 min^(-1) = 6.93 × 10^(-2) min^(-1). Option A and D have incorrect orders of magnitude, and B has the wrong coefficient.

Lucas reagent (HCl/ZnCl2) reacts fastest with tertiary alcohols like (CH3)3COH (tert-butanol). Secondary alcohols react moderately, and primary alcohols react very slowly or not at all.

Both compounds are ethers with molecular formula C4H10O. Diethyl ether (C2H5-O-C2H5) and methyl isopropyl ether (CH3-O-CH(CH3)2) differ only in the alkyl groups attached to the oxygen atom. This is metamerism - a type of structural isomerism where the functional group remains the same but the alkyl groups on either side vary.

The dry distillation of calcium acetate with soda lime (NaOH + CaO) produces methane through decarboxylation. Each acetate ion loses CO2 to form a methyl group, which then combines with hydrogen from the reagents to give methane (CH4). This is a classic laboratory method for alkane synthesis.

IUPAC name of CH₃-O-C₂H₅ is methoxyethane.

When calcium salts of two different carboxylic acids are heated together (dry distillation), they form a mixed ketone. Calcium acetate provides CH3CO- and calcium benzoate provides C6H5CO-, giving acetophenone (CH3-CO-C6H5). This is a ketonic synthesis reaction.

Primary amines have a lone pair of electrons on the nitrogen atom, which they can donate to electron-deficient species (Lewis acids). This makes them Lewis bases. R-NH2 acts as a nucleophile in most reactions and can coordinate to metal ions or accept protons.

The acidity of haloacetic acids increases with the number of electron-withdrawing halogen atoms. More chlorines stabilize the conjugate base better by dispersing the negative charge through inductive effect. Trichloroacetic acid (Cl3CCOOH) is strongest because it has three -I effect groups, followed by dichloro, then chloro, then unsubstituted acetic acid.

Calcium oxalate is the primary component of most kidney stones. It precipitates when calcium and oxalate ion concentrations exceed solubility product in urine. These crystals form hard, stony deposits that can obstruct urinary flow. The other compounds are not typical kidney stone constituents.

Rancid butter develops its characteristic foul smell due to bacterial hydrolysis of triglycerides, releasing free fatty acids. Butyric acid (C3H7COOH, butanoic acid) is particularly volatile and malodorous. Caproic, stearic, and palmitic acids are either not produced in significant quantities or are less odorous.

Nitration of benzene requires the nitronium ion (NO2+) as the electrophile. This species is generated in situ by the reaction of concentrated nitric acid with concentrated sulfuric acid, which acts as a dehydrating agent. The nitronium ion attacks the electron-rich benzene ring in an electrophilic aromatic substitution reaction.

Proteins are biopolymers composed of amino acid monomers linked by peptide bonds (amide bonds between -NH2 and -COOH groups). The peptide bond formation creates polypeptide chains, which fold into functional three-dimensional protein structures. All other options describe incorrect polymer types.

Antipyretics are medications that reduce elevated body temperature (fever) by acting on the hypothalamic heat-regulating center. Common examples include paracetamol (acetaminophen), aspirin, and ibuprofen. They should not be confused with analgesics (pain relievers) or antibodies (immune proteins).

Rabies is caused by the rabies virus, which attacks the central nervous system. Therefore, treatment requires antiviral medications. Antibacterial drugs target bacteria, antifungal drugs target fungi, and antibodies are immune proteins produced by the body - none of these are effective against viral infections.