120 g of an organic compound that contains only carbon and hydrogen gives 330 g of CO₂ and 270 g of water on complete combustion. The percentage of carbon and hydrogen, respectively are

The energy of one mole of photons of radiation of wavelength 300 nm is

(Given : h = 6.63 $$\times$$ 10^$$-$$34 J s, N_A = 6.02 $$\times$$ 10²³ mol^$$-$$1, c = 3 $$\times$$ 10⁸ m s^$$-$$1)

The correct order of bond orders of $${C_2}^{2 - }$$, $${N_2}^{2 - }$$ and $${O_2}^{2 - }$$

At 25$$^\circ$$C and 1 atm pressure, the enthalpies of combustion are as given below :

Substance	$${H_2}$$	C (graphite)	$${C_2}{H_6}(g)$$
$${{{\Delta _c}{H^\Theta }} \over {kJ\,mo{l^{ - 1}}}}$$	$$ - 286.0$$	$$ - 394.0$$	$$ - 1560.0$$

The enthalpy of formation of ethane is

For a first order reaction, the time required for completion of 90% reaction is 'x' times the half life of the reaction. The value of 'x' is

(Given : ln 10 = 2.303 and log 2 = 0.3010)

Metals generally melt at very high temperature. Amongst the following, the metal with the highest melting point will be :

PCl₅ is well known, but NCl₅ is not. because,

Transition metal complex with highest value of crystal field splitting ($$\Delta$$₀) will be :

Arrange the following carbocations in decreasing order of stability.

Given below are two statements :

Statement I : The presence of weaker $$\pi$$-bonds make alkenes less stable than alkanes.

Statement II : The strength of the double bond is greater than that of carbon-carbon single bond.

In the light of the above statements, choose the correct answer from the options given below :

Which of the following reagents / reactions will convert 'A' to 'B' ?

Hex-4-ene-2-ol on treatment with PCC gives 'A'. 'A' on reaction with sodium hypoiodite gives 'B', which on further heating with soda lime gives 'C'. The compound 'C' is :

The conversion of propan-1-ol to n-butylamine involves the sequential addition of reagents. The correct sequential order of reagents is

In the flame test of a mixture of salts, a green flame with blue centre was observed. Which one of the following cations may be present?

A company dissolves 'x' amount of CO₂ at 298 K in 1 litre of water to prepare soda water. X = __________ $$\times$$ 10^$$-$$3 g. (nearest integer)

(Given : partial pressure of CO₂ at 298 K = 0.835 bar.

Henry's law constant for CO₂ at 298 K = 1.67 kbar.

Atomic mass of H, C and O is 1, 12, and 6 g mol^$$-$$1, respectively)

PCl₅ dissociates as

PCl₅(g) $$\rightleftharpoons$$ PCl₃(g) + Cl₂(g)

5 moles of PCl₅ are placed in a 200 litre vessel which contains 2 moles of N₂ and is maintained at 600 K. The equilibrium pressure is 2.46 atm. The equilibrium constant K_p for the dissociation of PCl₅ is __________ $$\times$$ 10^$$-$$3. (nearest integer)

(Given : R = 0.082 L atm K^$$-$$1 mol^$$-$$1; Assume ideal gas behaviour)

The resistance of a conductivity cell containing 0.01 M KCl solution at 298 K is 1750 $$\Omega$$. If the conductivity of 0.01 M KCl solution at 298 K is 0.152 $$\times$$ 10^$$-$$3 S cm^$$-$$1, then the cell constant of the conductivity cell is ____________ $$\times$$ 10^$$-$$3 cm^$$-$$1.

Manganese (VI) has ability to disproportionate in acidic solution. The difference in oxidation states of two ions it forms in acidic solution is ____________.

0.2 g of an organic compound was subjected to estimation of nitrogen by Dumas method in which volume of N₂ evolved (at STP) was found to be 22.400 mL. The percentage of nitrogen in the compound is _________. [nearest integer]

(Given : Molar mass of N₂ is 28 g mol^$$-$$1. Molar volume of N₂ at STP : 22.4 L)

Consider the above reaction. The number of $$\pi$$ electrons present in the product 'P' is __________.

In alanylglycyl leucyl alanyl valine, the number of peptide linkages is ___________.