Consider the following reaction: 2 C 6 H 6 (l) + 15 O 2 (g) → 12 CO 2 (g) + 6 H 2 O (g) ∆Hº = – 6278 kJ What volume of benzene (C 6 H 6 , d = 0.880 g/mL, molar mass = 78.11 g/mol) is necessary to evolve 5.19 x 10 9 kJ of heat?

Here it says consider the following reaction. Here we have 2 moles of benzene reacting with 15 moles of oxygen gas to produce 12 moles of carbon dioxide gas, plus 6 moles of water vapor. Associated with it is our delta h of reaction as negative 6,278 kilojoules. Here it says, what volume of benzene, which is c 6h6, that has a density of 0.880 grams per milliliter and a molar mass of 78.11 grams per mole, is necessary to evolve 5.19 times 10 to the 9 kilojoules of heat. So first of all, this talking about heat, heat is q, but q is also equal to delta h. So here they're giving us delta h and they want me to determine the volume, so milliliters of benzene. So that's what our missing information is. We're gonna start out with 5.19 times 10 to the negative 9 kilojoules. Now realize from the information given to us that here is another kilojoule. We're gonna bring that down and we're gonna realize that that many kilojoules released is attached to 2 moles of benzene. So that's for every 2 moles of benzene. Kilojoules cancel out, now I have moles of benzene. I need to get to volume in milliliters of benzene, which means density is gonna have to be incorporated in some way. But density has within it grams. So what I need to do next is I need to convert moles of benzene into grams of benzene. One mole of benzene, we're told weighs 78.11 grams. Now that I have the grams of benzene, I can say that the density of benzene is 0.880 grams of benzene for every 1 milliliter of benzene. So grams cancel out and I'll have milliliters. Here I go I'm going to isolate 3 sig figs based on the values given to me. So this comes out to 7.34 times 10 to the 7 milliliters of benzene as the final volume for

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Multiple Choice

Consider the following reaction:
2 C₆H₆ (l) + 15 O₂ (g) → 12 CO₂ (g) + 6 H₂O (g) ∆Hº = – 6278 kJ
What volume of benzene (C₆H₆, d = 0.880 g/mL, molar mass = 78.11 g/mol) is necessary to evolve 5.19 x 10⁹ kJ of heat?

1.47 x 10⁸ mL

5.19 x 10⁹ mL

7.34 x 10⁷ mL

9.51 x 10⁹ mL

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Verified step by step guidance

Identify the given data: The reaction releases 6278 kJ of heat per 2 moles of C6H6. We need to find the volume of C6H6 required to release 5.19 x 10^9 kJ of heat.

Calculate the moles of C6H6 needed to release 5.19 x 10^9 kJ of heat using the ratio from the reaction's enthalpy change: \( \frac{5.19 \times 10^9 \text{kJ}}{6278 \text{kJ}} \times 2 \text{ moles of C6H6} \).

Convert the moles of C6H6 to grams using its molar mass: \( \text{moles of C6H6} \times 78.11 \text{ g/mol} \).

Convert the mass of C6H6 to volume using its density: \( \frac{\text{mass of C6H6}}{0.880 \text{ g/mL}} \).

The calculated volume will give you the amount of benzene needed to evolve 5.19 x 10^9 kJ of heat. Compare this volume with the given options to find the correct answer.