Consider the reactions: C(s)+2H2(g) xrightarrowCH4(g); Δ H=-x kcal C(g)+4H(g) xrightarrowCH4(g); Δ H=- y kcal CH4(g) xrightarrowCH3(g)+H(g); Δ H=+ z kcal The bond energy of C?H bond is:

Question

Consider the reactions: C(s)+2H2(g) xrightarrowCH4(g); Δ H=-x kcal C(g)+4H(g) xrightarrowCH4(g); Δ H=- y kcal CH4(g) xrightarrowCH3(g)+H(g); Δ H=+ z kcal The bond energy of C?H bond is: (A)  texty textkcal textmo textl-1  (B)  z textkcal textmo textl-1  (C)  (x/4) textkcal textmo textl-1  (D)  (y/2) textkcal textmo textl-1

Tardigrade Admin · Accepted Answer

CH4(g) xrightarrowCH3(g)+H(g); Δ H=+z kcal In this reaction, one C?H bond is breaking hence, Δ H represent the bond dissociation energy of C?H bond. Hence C?H bond energy is z kcal.

Q. Consider the reactions: $C (s) + 2 H_{2} (g) C H_{4} (g);$ $Δ H = - x k c a l$ $C (g) + 4 H (g) C H_{4} (g);$ $Δ H = - y k c a l$ $C H_{4} (g) C H_{3} (g) + H (g);$ $Δ H = + z k c a l$ The bond energy of C?H bond is:

$y kcal mo l^{- 1}$

$z kcal mo l^{- 1}$

$\frac{x}{4} kcal mo l^{- 1}$

$\frac{y}{2} kcal mo l^{- 1}$

$C H_{4} (g) C H_{3} (g) + H (g);$ $Δ H = + z k c a l$ In this reaction, one C?H bond is breaking hence, $Δ H$ represent the bond dissociation energy of C?H bond. Hence C?H bond energy is z kcal.

Q. Consider the reactions: C(s)+2H2​(g)​CH4​(g); ΔH=−xkcal C(g)+4H(g)​CH4​(g); ΔH=−ykcal CH4​(g)​CH3​(g)+H(g); ΔH=+zkcal The bond energy of C?H bond is:

ykcalmol−1

zkcalmol−1

4x​kcalmol−1

2y​kcalmol−1