17.77 g of ethane (30.07 g/mol) needed to react to produce 461 kJ of heat.
What is heat?
When a reaction is occurred, some amount of heat produced or released, which is called the heat produced.
Given the reaction, 2C₂H₆ (g) + 7O₂(g) → 4CO₂(g) + 6H₂O (g) ΔH = -1560 kJ
2 moles of ethane produce -1560 kJ heat
so, for 461 KJ heat,
[tex]\dfrac{461}{1560} \times 2 = 0.591[/tex]
Now, the mass of ethane is [tex]0.591 \times 30.07 = 17.77 g[/tex]
Thus, the mass of ethane, 17.7 grams.
Learn more about heat
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