From the following data,the enthalpy of dilution of $KCl$ will be ............ $kJ$.
$KCl_{(s)} + 20H_2O \to KCl(20H_2O); \Delta H = + 15.90 \ kJ$
$KCl_{(s)} + 200H_2O \to KCl(200H_2O); \Delta H = + 18.58 \ kJ$

One mole of an ideal gas is allowed to expand freely and adiabatically into vacuum until its volume has doubled. Which of the following statements is $NOT$ true concerning this expansion?

$A$ gas (Molar mass $= 280 \ g \ mol^{-1}$) was burnt in excess $O_2$ in a constant volume calorimeter and during combustion the temperature of calorimeter increased from $298.0 \ K$ to $298.45 \ K$. If the heat capacity of calorimeter is $2.5 \ kJ \ K^{-1}$ and enthalpy of combustion of gas is $9 \ kJ \ mol^{-1}$,then the amount of gas burnt is $...... \ g$. (Nearest Integer)

For the reactions,$C + O_2 \to CO_2; \Delta H = -393 \ J$
$2Zn + O_2 \to 2ZnO; \Delta H = -412 \ J$

The $\Delta E^o$ of combustion of $2-$methylpropene is $-X \ kJ \ mol^{-1}$. The value of $\Delta H^o$ is

Which of the following is incorrect?