Question

Benzene (c6h6) burns in air to produce co2 and liquid water. calculate heat released in kj per gram of the compound reacted with oxygen. the standard enthalpy of formation of benzene is 49.04 kj/mol.

Answer 1

Answer: -41.83kg/g

Step 1 : set equations and balance

Step 2 : standard enthalpies of for all

Step 3: products site- reactants side

Step 4: conversion to gram

Answer 2

Answer:Heat released in kilo Joule per gram of benzene when reacted with oxygen is 0.628 kJ/g.

Explanation:

The standard enthalpy of formation of benzene is 49.04 kJ/mol. Same amount of energy will be released on  combustion of 1 mol of benzene.

$2C_6H_6+8O_2\rightarrow 6CO_2+4H_2O,\Delta H=-49.04kJ/mol$

Mass of 1 mol of benzene = 78 g

1 mole of benzene on combustion gives = 49.04 kJ

78 g of benzene on combustion gives = 49.04 kJ

1 g of benzene on combustion will give = $\frac{49.04 kJ}{78 g}=0.628 kJ$

Heat released in kilo Joule per gram of benzene when reacted with oxygen is 0.628 kJ/g.