Calculate the heat of combustion of glucose from the following data - (i) C text (graphite) + O 2 (g) longrightarrow CO 2(g), Δ H =-395.0 kJ (ii) H 2 (g) +1 / 2 O 2 longrightarrow H 2 O (l), Δ H =-269.5 kJ (iii) 6 C text (graphite) +6 H 2 (g) +3 O 2 (g) longrightarrow C 6 H 12 O 6 (s), Δ H =-1170 kJ

Question

Calculate the heat of combustion of glucose from the following data - (i) C text (graphite) + O 2 (g) longrightarrow CO 2(g), Δ H =-395.0 kJ (ii) H 2 (g) +1 / 2 O 2 longrightarrow H 2 O (l), Δ H =-269.5 kJ (iii) 6 C text (graphite) +6 H 2 (g) +3 O 2 (g) longrightarrow C 6 H 12 O 6 (s), Δ H =-1170 kJ (A)  (B)  (C)  (D)

Tardigrade Admin · Accepted Answer

From given, (i) 6 C +6 O 2 longrightarrow 6 CO 2 ; Δ H =6 ×(-395.0) kJ (ii) 6 H 2 (g) +(6/2) O 2 longrightarrow 6 H 2 O; Δ H =6 ×(-269.5) kJ ((iii) C 6 H 12 O 6 longrightarrow 6 C +6 H 2+3 O 2 ; Δ H =1170 kJ/(i) + (ii) + (iii) C 6 H 12 O 6+6 O 2 longrightarrow 6 CO 2+6 H 2 O); Δ H ; 6 ×(-395.0)+6 ×(-269.5)+1170 =-2370-1617+1170 =-2817 kJ

Q. Calculate the heat of combustion of glucose from the following data - (i) C(graphite) ​+O2​(g)⟶CO2​(g),ΔH=−395.0kJ (ii) H2​(g)+1/2O2​⟶H2​O(l),ΔH=−269.5kJ (iii) 6C(graphite) ​+6H2​(g)+3O2​(g)⟶C6​H12​O6​(s),ΔH=−1170kJ

From given, (i) 6C+6O2​⟶6CO2​;ΔH=6×(−395.0)kJ (ii) 6H2​ (g) +26​O2​⟶6H2​O; ΔH=6×(−269.5)kJ (i)+(ii)+(iii)C6​H12​O6​+6O2​⟶6CO2​+6H2​O(iii)C6​H12​O6​⟶6C+6H2​+3O2​;ΔH=1170kJ​; ΔH;6×(−395.0)+6×(−269.5)+1170 =−2370−1617+1170 =−2817kJ