At Constant volume, the heat required to raise the temperature of $$4.48 \mathrm{~L}$$ of an ideal gas at STP by $$15^{\circ} \mathrm{C}$$ is 12.0 calories. The $$\mathrm{C_p}$$ of the gas is _____________ $$(\mathrm{R}=2 \mathrm{~Cal} \mathrm{~kg}^{-1} \mathrm{~mol}^{-1})$$
$$ 1 \mathrm{~cm}^3 \text { of } 0.01 \mathrm{~M} \mathrm{~HCl} \text { is added to } 1 \mathrm{~L} \text { of } \mathrm{NaCl} \text { solution. The } \mathrm{pH} \text { of the resulting solution is: } $$
An organic compound with molecular formula $$\mathrm{C}_3 \mathrm{H}_5 \mathrm{N}$$ on hydrolysis gives compound '$$\mathrm{X}$$' which on treatment with $$\mathrm{Cl}_2 / \mathrm{P}$$ gives compound '$$\mathrm{Y}$$'. Compound '$$\mathrm{Y}$$' on reaction with $$\mathrm{NH}_3$$ gives '$$\mathrm{Z}$$'. The compound '$$\mathrm{Z}$$' is :
Which of the following carbanions is the least stable?