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Using the given data, calculate heat of combustion of ethene

Bond	Bond energy (kJ `mol^(–1)`)
C = C C—H O = O C = O O—H	619 414 499 724 660

The coordination number of a central atom in a molecules or crystal is the number of its nearest neighbours. The coordination number of sdium in `Na_2O` is

WH Bragg pointed out that the scattering of X-rays by crystals could be considered as reflection from successive planes of atoms in the crystals. Which of the following equation represents Braggs equation

The equivalent weight of `KMnO_4` in acidic medium will be

Hydrogen reacts with different elements to form variety of hydrides. Their stability depends upon lattice energy. and ionic character. Covalent hydride is most common type pf hydrides. Find from the following which is polymeric hydride

Hg shows two oxidation states (I) and (II) in its compound. Chemistry of Hg(I) is intersecting as `Hg^+` does not exist. `Hg_2Cl_2` on treatement with alkali gives red solid which one is that

`10 Cl^- (aq) + 2MnO_4^- (aq) + 16h=(aq) ⇌ 5Cl_2(g) + 2Mn^(2+)(aq) + 8H_2O(l)`. The value of Eº for this reaftion is 0.15 V. What is the value of the equilibrium constant (K) for this reaction ?

Among the following species, identify the isostructural pairs
`[NF_3, NO_3^-, BF_3, H_3O^+, HN_3]`

Choose the incorrect statement regarding P

The Witting reaction is a chemical reaction of an aldehyde or ketone with a triphenyl phosphonium slide (Witting reagent). The product obtained by the reaction of cyclopentanone with Witting reagent is

The most suitable method of separation of a mixture of ortho and para nitrophenol in the ratio 1 : 1 is

Aryl halides are extremely less reactive towards nucleophilic substition due to the following reasons

a. Resonance effect
b. Instantibility of phenyl cation
c. Because of possible repulsive

Chose the correct order of reactivity towards nucleophilic substitution reactin of following compounds

Correct order of basic stragth is

The substrate obtained in between the reactant and the product. Sometimes, the intermediates may be quite stable enough. Intermediate involved in formation of pinacolone is

There are substantial solvent effects in the Claisen reaction, more polar solvents tend to accelerate to a greater extend. Which of the following reaction is and example of Claisen rearrangement

In phenol the —OH group shows +R and –I effects and here activate the benzene ring towards electrophilic substitution reactions. Phenol on reaction with HCN/ HCl in presence of `AlCl_3` produces

A 0.025 m Solution of monobasic acid had a freezing point of 0.060ºC. The `pK_a` for the acid is `(K_b = 1.86` Kkg `mol^(–1)`)

A hormone is a class of regulatory biochemicals produced in particular part of organisms by specific cells, glands or tissue and then transported by the blood stream to the other part of the body. Which of the following protein acts as a hormone

The most basic property of a polymer is the idnetify of its constitent monomers. A second set of properties, known as microstructure essentially describe the arrangement of these monomers within the polymer at the scale of a single chain. Orlon is a polymer of

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