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If the heat of combustion for a specific compound is −1160.0 kJ/mol and its molar mass is 86.47 g/mol, how many grams of this compound must you burn to release 541.20 kJ of heat?

User Shauna
by
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1 Answer

6 votes

Answer:

40.34 g

Step-by-step explanation:

First, we divide the heat to release by the heat of combustion to obtain the required moles of compound:

541.20 kJ/(1160.00 kJ/mol) = 0.4665 mol

So, we have to burn approximately 0.47 mol of the compound. We convert the moles to mass in grams by using the molar mass:

mass = molar mass x moles = 86.47 g/mol x 0.4665 mol = 40.34 g

Therefore, you must burn 40.34 grams of the compound to release 541.20 kJ of heat.

User Ashish Satpute
by
8.4k points
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