The total volume of hydrogen gas needed to fill the hindenburg was 2.00 × 108 l at 1.00 atm and 25.° c. how much energy was evolved when it burned?

Answer : The energy evolved when it burned was,

Solution :

First we have to calculate the moles of hydrogen gas by using ideal gas equation.

where,

P = pressure of gas = 1 atm

V = volume of gas =

T = temperature of gas =

R = gas constant = 0.0821 Latm/moleK

n = number of moles of gas

Now put all the given values in the above formula, we get the moles of hydrogen gas.

Now we have to calculate the amount of energy evolved.

The combustion reaction of hydrogen will be,

The enthalpy of combustion of hydrogen is -286 KJ/mole. (standard value)

As 1 mole of hydrogen gas burned it evolved energy = -286 KJ

So, of hydrogen gas burned it evolved energy =

Therefore, the energy evolved when it burned was,

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hope this : -)

tony (lordcaos066)

thats how its supposed to be