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3 years ago

Calculate the average molar bond enthalpy of the carbon-hydrogen bond in a ch4 molecule.

Chemistry

2 answers:

MatroZZZ [7]3 years ago

8 0

Answer:

415.825 kJ/mol.

Explanation:

Average enthalpy = $\Delta H_f(CH_4)-4\Delta H_f(H)-\Delta H_f(C)$

Now, $\Delta H_f(CH_4)=-74.6 kJ/mol$

$\Delta H_f(H)=218 kJ/mol$

$\Delta H_f(C)=716.7 kJ/mol$

( SOURCE INTERNET)

Putting all these values above.

We get,

Average enthalpy=-1663.3 kJ.

Therefore, averagemolar bond enthalpy= $\dfrac{1663.3 }{4}=415.825\ kJ/mol.$

Hence, this is the required solution.

balandron [24]3 years ago

7 0

<span>The average molar bond enthalpy of the carbon-hydrogen bond in a CH4 molecule is 416 KJ/mol. (+716.7 + (4 x 218) - (- 74.6) ) / 4 = + 1663.3 / 4 = 416</span>

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3 years ago

Determine whether each phrase describes carboxylic acids or esters.

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Answer:

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3 years ago

A 46.9 gram sample of a substance has a volume of about 3.5 centimeters3. It is solid at a room temperature of 23ºC. Out of the

horrorfan [7]

Answer : (C) Hafnium is the most likely identity of the given substance.

Solution : Given,

Mass of given substance (m) = 46.9 g

Volume of given substance (V) = 3.5 $Cm^{3}$

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Formula used :

$Density=\frac{\text{Mass of given substance}}{\text{Voume of given substance}}$

Now,put all the values in this formula, we get

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3 years ago

Read 2 more answers

Natural gas is stored in a spherical tank at a temperature of 13°C. At a given initial time, the pressure in the tank is 117 kPa

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Answer:

1. the absolute pressure in the tank before filling = 217 kPa

2. the absolute pressure in the tank after filling = 312 kPa

3. the ratio of the mass after filling M2 to that before filling M1 = 1.44

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