Isobars are atoms with

Using the standard electrode potentials given below identify the correct statements from the following.
\[
\begin{aligned}
\mathrm{Fe}^{2+}+2 e^{-} \longrightarrow \mathrm{Fe} ; E^{\circ} & =-0.44 \mathrm{~V} \\
\mathrm{Cu}^{2+}+2 e^{-} \longrightarrow \mathrm{Cu} ; E^{\circ} & =+0.34 \mathrm{~V} \\
\mathrm{Ag}^{+}+e^{-} \longrightarrow \mathrm{Ag} ; E^{\circ} & =+0.80 \mathrm{~V}
\end{aligned}
\]
(i) Copper can displace iron from \(\mathrm{FeSO}_4\) solution.
(ii) Iron can displace copper from \(\mathrm{CuSO}_4\) solution.
(iii) Silver can displace copper from \(\mathrm{CuSO}_4\) solution.
(iv) Iron can displace silver from \(\mathrm{AgNO}_3\) solution.

Identify the species, which does not exist?

At \(300 \mathrm{~K}\) the enthalpy change for the following reaction is \(-2800 \mathrm{~kJ} \mathrm{~mol}^{-1}\)

Which of the following pairs of ions are colourless?

An element with molar mass \(2.7 \times 10^{-2} \mathrm{~kg} \mathrm{~mol}^{-1}\) forms a cubic unit cell with edge length of \(405 \mathrm{pm}\). If its density is \(2.7 \times 10^3 \mathrm{~kg} \mathrm{~m}^{-3}\), the nature of cubic unit cell is :
\[
\left(\mathrm{N}_{\mathrm{A}}=6.02 \times 10^{23} \mathrm{~mol}^{-1}\right)
\]

The element with maximum bond-energy

If the coordinates of the ends of a focal chord of the parabola \(x^2=4\) ay are \(\left(x_1, y_1\right)\) and \(\left(x_2, y_2\right)\), then

Calculate the energy associated with the second orbit of \(\mathrm{Li}^{+}\)and find it's radius?

Assuming \(|x|\) to be so small, that \(x^2\) and higher powers of \(x\) can be neglected, then \(\frac{\sqrt{1+x}+(1-x)^{3 / 2}}{(1+x)+\sqrt{1+x}}=\)

Two coherent light sources having intensity in the ratio \(2 \mathrm{x}\) produce an interference pattern. Then the value of \(\frac{I_{\max }-I_{\min }}{I_{\max }+I_{\min }}\) will be

A, B, C are three horses participating in a race. The Probability of horse A to win the race is twice that of horse B and probability of horse B to win is twice that of horse \(\mathrm{C}\). Then the probabilities of horses A, B and C to win the race are respectively

A body of mass \(m\) is suspended to an ideal spring of force constant \(k\). The expected change in the position of the body due to an additional force \(F\) acting vertically downwards is