8.1. Organic chemistry Nomenclature of organic compounds — Chemistry STD 11 Science — Question

$\begin{array}{l} Cl - Cl ( g ) \longrightarrow Cl ^*( g )+ Cl ^*( g ) \Delta H ^{\circ}=58 kcal mol ^{-1} \\ H _3 C - Cl ( g ) \longrightarrow H _3 C ^*( g )+ Cl ^{\circ}( g ) \Delta H ^{\circ}=85 kcal mol ^{-1} \\ H - Cl ( g ) \quad \longrightarrow H ^*( g ) \quad+ Cl ^*( g ) \Delta H ^{\circ}=103 kcal mol ^{-1} \\\end{array}$

($1$) Correct match of the $C - H$ bonds (shown in bold) in Column $J$ with their BDE in Column $K$ is

$(A)$ $P - iii, Q - iv, R - ii, S - i$

$(B)$ $P - i, Q - ii, R - iii, S - iv$

$(C)$ $P - iii, Q - ii, R - i, S - iv$

$(D)$ $P - ii, Q - i, R - iv, S - iii$

($2$) For the following reaction

$CH _4( g )+ Cl _2( g ) \xrightarrow{\text { light }} CH _3 Cl ( g )+ HCl ( g )$

the correct statement is

$(A)$ Initiation step is exothermic with $\Delta H ^{\circ}=-58 kcal mol ^{-1}$

$(B)$ Propagation step involving ${ }^{\circ} CH _3$ formation is exothermic with $\Delta H ^{\circ}=-2 kcal mol ^{-1}$.

$(C)$ Propagation step involving $CH _3 Cl$ formation is endothermic with $\Delta H ^{\circ}=+27 kcal mol ^{-1}$.

$(D)$ The reaction is exothermic with $\Delta H ^{\circ}=-25 kcal mol ^{-1}$.

$N_2(g) + 3H_2(g) \to 2NH_3(g)$ is

$-\,92.38\,KJ$ at $298\,K$ . The internal energy change $\Delta U$ at $298\,K$ is.....$KJ$

$\Delta H_f^o[CO_2,g] = -394 \,kJ/mol$ 

$\Delta H_f^o[H_2O,l] = -286\, kJ/mol$ 

$\Delta H_f^o [propene ,g] = 20\,kJ/mol$ 

cyclopropane $(g)$ $\to$ propene $(g)$ ; $\Delta H^o_{isomerisation} = $ $-33\,kJ/mol$.
Calculate $\Delta H^o_{combustion}$ [cyclopropane, $(g)$]

......$ kJ/mol$