Chemistry Test ...

The radius ratio of an ionic solid \(\left(\mathrm{A}^{+} \mathrm{B}^{-}\right)\) is \(0.69 .\) What is the coordination number of \(B^{-} ?\)

In which of the following compounds, the Fluorine atom is not placed axially in a trigonal bipyramidal geometry?

Consider (i) CO₂,(ii) CCL₄ ,(iii) C₆Cl₆ and (iv) CO and tell which of the following statements is correct?

Nitrogen and hydrogen react to produce ammonia in the Haber process:

\(\mathrm{N}_{2}(\mathrm{g})+3 \mathrm{H}_{2}(\mathrm{g}) \rightleftharpoons 2 \mathrm{NH}_{3}(\mathrm{g})\) Calculate the enthalpy of formation of ammonia.

The mass number of an element is 27. If it has 14 neutrons then valence shell of this element is :

On heating pyrollusite with KOH in presence of air we get ?

Arrange the following ions in order of their magnetic moment:

(i) \(\mathbf{V}^{4+}(\mathbf{i i}) \mathbf{M} \mathbf{n}^{4+}(\mathbf{i i i}) \mathbf{F} \mathbf{e}^{3+}(\mathbf{i v}) \mathbf{N} \mathbf{i}^{2+}\)

[Atomic number of V=23, Mn=25, Fe=26, Ni=28]

If 150 kJ of energy is needed for a man to walk a distance of 1 km, then how much glucose does one have to consume to walk a distance of 5 km, provided that only 30% of energy is available for muscular work? (The enthalpy of combustion of glucose is 3000 kJ mol^-1.)

The heat of combustion of \(\mathrm{CH}_{4}(\mathrm{g})\), \(\mathrm{C}\) (graphite) and \(\mathrm{H}_{4}\) (g) are respectively \(-20 \mathrm{k}\).cal, \(-40 \mathrm{k} .\) cal and \(-10 \mathrm{k}\).cal. The heat of formation of \(\mathrm{CH}_{4}\) is

The species which by definition has zero standard molar enthalpy of formation at 298 K is :