Chemistry Test-...

Which of the following reaction is most exothermic?

Identify the IUPAC of dexamethasone:

The vapour pressure of a solvent decreased by 10 mm of mercury when a non-volatile solute was added to the solvent. The mole fraction of the solute in the solution is 0.2. What should be the mole fraction of the solvent, if the decrease in the vapour pressure is to be 20 mm of mercury?

Which one of the following is responsible for the depletion of the ozone layer in the upper strata of the atmosphere?

Standard enthalpies of formation of CO₂(g), CO(g), N₂O(g) and NO₂(g) in kJ/mol are -393, -110, 81 and 34, respectively. What is the value of ∆H(in kJ) in the following reaction?

2NO₂(g) + 3CO (g)N₂O (g) + 3CO₂(g)

The enthalpy of combustion of methane, graphite and dihydrogen at \(298 \mathrm{~K}\) are \(-890.3 \mathrm{~kJ} \mathrm{~mol}^{-1},-393.5 \mathrm{~kJ} \mathrm{~mol}^{-1}\), and \(-285.8 \mathrm{~kJ} \mathrm{~mol}^{-1}\) respectively. Enthalpy of formation of \(\mathrm{CH}_{4}(\mathrm{g})\) will be:

Two different first order reactions have rate constants \(\mathrm{k}_{1}\) and \(\mathrm{k}_{2}\) at \(\mathrm{T}_{1}\left(\mathrm{k}_{1}>\mathrm{k}_{2}\right)\). If temperature is increased from \(\mathrm{T}_{1}\) to \(\mathrm{T}_{2}\), then new constants become \(\mathrm{k}_{3}\) and \(\mathrm{k}_{4}\) respectively. Which among the following relations is correct?

A diatomic molecule has a dipole moment of 1.2 D. If its distance is 1.0 Å, what fraction of an electronic charge, e exist on each atom?

Which element has three shells which are completely filled with electrons?

Ratio of number of faradays of electricity required to deposit magnesium, aluminium and sodium in equimolar ratio an electrolysis of their respective molten salts is:

On shaking H₂O₂ with acidified potassium dichromate and ether, the ethereal layer becomes:

The solution of H₂O₂ can be stored for a long time at room temperature. However, bubbles of oxygen form as soon as a drop of bromine is added. The role of bromine for the reaction 2H₂O₂(aq) → 2H₂O(l) + O₂(g) is:

A complex has the molecular formula \(\mathrm{Co} .5 \mathrm{NH}_{3} . \mathrm{NO}_{2} . \mathrm{Cl}_{2}\). One mole of this complex produces three moles of ions in an aqueous solution. On reacting this solution with excess of \(\mathrm{AgNO}_{3}\) solution, we get 2 moles of white ppt. The complex is:

Which molecule is relatively more stable?

Ellingham diagram represents the change in: