Consider the reaction, C₂H₄(g)+ H₂(g)$\rightarrow$C₂H₆(g), where $\Delta$H = -137 kJ. How many kilojoules are released when 55.3 g of C₂H₄reacts?

Question

Quizplus · Accepted Answer

The given reaction releases energy (exothermic) as H = -137 kJ. We need to find the amount of energy released when 55.3 g of C₂H₄ reacts. The first step is to calculate the moles of C₂H₄ using its molar mass: Molar Mass of C₂H₄ = 12 + 32 + 1 + 12 + 32 + 1 + 14 + 32 + 1 + 16 = 173 g/mol Number of moles of C₂H₄ = 55.3 g / 173 g/mol = 0.319 moles According to the balanced equation, 1 mole of C₂H₄ releases 137 kJ of energy. Therefore, 0.319 moles of C₂H₄ will release: Energy released = 0.319 moles x 137 kJ/mole = 43.74 kJ The answer in kJ should be rounded off to 3 significant figures because the given H value has 3 significant figures. Therefore, the answer is 270 kJ.

Consider the Reaction, C2H4(g)+ H2(g) →\rightarrow→ C2H6(g), Where Δ\DeltaΔ H = -137 KJ

Consider the Reaction, C₂H₄(g)+ H₂(g) $\rightarrow$ C₂H₆(g), Where $\Delta$ H = -137 KJ