Class 12th

The difference between spin only magnetic moment value of $\left[Co{\left(H_{2}O\right)}_{6}C{l}_{2}andCr{\left(H_{2}O\right)}_6\right]C{l}_3$  is _______________.

Let A = $\left|\begin{array}{ccc}\hfill 1\hfill & \hfill 1\hfill & \hfill 1\hfill \end{array}\right|$ and B = $\begin{array}{ccc}\hfill 9^2\hfill & \hfill -10^2\hfill & \hfill 11^2\hfill \\ \hfill 12^2\hfill & \hfill 13^2\hfill & \hfill -14^2\hfill \\ \hfill -15^2\hfill & \hfill 16^2\hfill & \hfill 17^2\hfill \end{array}$ , then the value of A'BA is:

For a reaction A--> 2B + C the half lives are 100s and 50s when the concentration of reactant A is 0.5 and 1.0 mol L^-1 respectively. The order of the reaction is _____________. (Nearest (Integer)

The amount of charge in F (Faraday) required to obtain one mole of iron from Fe₃O₄ is __________. (Nearest Integer)

If z = x + iy satisfies $\left|z\right|-2=0and\left|z-i\right|-\left|z+5i\right|=0,then$

At 298 K, the equilibrium constant is 2 * 10¹⁵ for the reaction:

Cu(s) + 2Ag⁺(aq)   $\rightleftharpoons$ Cu²⁺(aq) + 2Ag(s)

The equilibrium constant for the reaction

$\frac{1}{2}C{u}^{2+}\left(ag\right)$ + Ag(s)    + Ag⁺ (aq)

is x * 10^-8. The value of x is _____________. (Nearest Integer)

When 800mL of 0.5 M nitric acid is heated in a beaker, its volume is reduced to half and 11.5g of nitric acid is evaporated. The molarity of the remaining nitric acid solution is x * 10^-2M. (Nearest Integer)

(Molar mas of nitric acid is 63g mol^-1)

For a series LCR circuit, I vs  curve is shown:

Choose the most appropriate answer from the options given below:

The minimum value of the sume of the squares of the roots of x² + (3 – a)x + 1 = 2a is

2.4g coal is burnt in a bomb calorimeter in excess of oxygen at 298 K and 1 atm pressure. The temperature of the calorimeter rises from 298 K to 300 K. The enthalpy change during the combustion of coal is -x kJ mol^-1. The value of x is ____________.

(Given : Heat capacity of bomb calorimeter 20.0 kJ K^-1. Assume coal to be pure carbon)