$3.0$ molal $NaOH$ solution has a density of $1.110 \, g/mL$. The molarity of the solution is

Iron sulphide is heated in air to form $A$, an oxide of sulphur. $A$ is dissolved in water to give an acid. The basicity of this acid is:

Which of the following has the maximum mass?

$K_2CS_3$ is called potassium ...... .

For the reaction: $N_{2(g)} + 3H_{2(g)} \rightarrow 2NH_{3(g)}$,$\Delta H = -24 \ \text{kcal}$ at $427 \ ^\circ\text{C}$ and $200 \ \text{atm}$. Calculate the magnitude of the internal energy change ($\Delta U$ in $\text{kcal}$),if $168 \ \text{g}$ of $N_2$ gas and $30 \ \text{g}$ of $H_2$ gas are allowed to react completely ($100\%$ reaction yield) to form $NH_3$ gas at $427 \ ^\circ\text{C}$ and $200 \ \text{atm}$.

Green compound $(A)$ on decomposition gives gases $(B)$ and $(C)$ along with a red-brown residue. $(B)$ and $(C)$ are acidic oxides of sulphur. Gas $(B)$ gives a positive test with $KMnO_4$.
$(C) + H_2SO_4 \to (D)$ $\xrightarrow{+ [O]} (E)$ $\xrightarrow{2H_2O} (F) + H_2SO_4$
$(F)$ $\xrightarrow{K_3[Fe(CN)_6] / KOH} (G)$ $\xrightarrow{Conc. H_2SO_4} (H) \text{ (Neutral oxide, poisonous)}$
Total number of $\sigma$ bonds in $(E)$ is: