All categories

3 years ago

The enthalpy of formation of CO2 at 25oC is -393.51 kJ/mol. What is the enthalpy of formation at 500 oC?

Chemistry

1 answer:

Kisachek [45]3 years ago

6 0

Answer:

-375.9_KJ/(mol)

Explanation:

H(T2 ) ≈ H(T1)+CPΔT

Specific heat of Carbon is 0.71 J/g K.

At 283.15 the heat capacity is 37.12 J/(mol*K)

Kirchhoff's law

H(T2 ) ≈ H(T1)+CPΔT

Where

H(T1) and H(T2 ) are the heat of formation of CO2 at temperatures T1 and T2

CP is the heat capacity

Thus we have and ΔT is the temperature change

H(T2 ) ≈ -393.51×10^3+CP×(500-25)

= -393.51×10^3+37.12×(500-25)

= -375878 J/(mol)

= -375.9KJ/(mol)

You might be interested in

What type of reaction is shown? PbO2 --> PbO + O2 *

Lerok [7]

Answer:

single replacement reaction.

3 0

4 years ago

1H2 + 2O2 -> 3Н2O.

makvit [3.9K]

Answer:

1H2 + O2 -> 2Н2O.

combination reaction.

7 0

3 years ago

A 1.00 g sample of n-hexane (C6H14) undergoes complete combustion with excess O2 in a bomb calorimeter. The temperature of the 1

Nadya [2.5K]

Answer:

-5,921x10⁶J/mol

Explanation:

Internal energy change (ΔU) for the reaction of combustion in the bomb calorimeter is:

ΔU = q calorimeter + q solution

Where:

q calorimeter is Ccal×ΔT (Ccal=4042J/°C) and (ΔT is 29,30°C-22,64°C=6,66°C)

q solution is c×m×ΔT (c= 4.184 J/g°C), (m=1502g H₂O), (ΔT is 29,30°C-22,64°C=6,66°C)

Replacing:

ΔU = 26920J + 41854J = 68774 J

This energy is per g of n-hexane, now, per mole of n-hexane:

$\frac{68774J}{1gHexane} *\frac{86,1g}{1mol}$ = -5,921x10⁶J/mol

-negative because the energy is produced-

I hope it helps!

5 0

4 years ago

Read 2 more answers

Will mark brainly AsAP

zhuklara [117]

Homeostasis helps organisms Maintain balance

4 0

3 years ago

Given that naphthalene is insoluble in water and sublimes easily upon heating, describe two different methods by which you could

Sunny_sXe [5.5K]

Based on solubilities you can separate naphthalene and NaCl by adding the mixture to a volume of water. NaCl is highly soluble in water, so it will dissolve completely, while the insoluble naphthalen will remain solid. Next your filter the solution, washing the solid with pure water to eliminate all the NaCl from it. The NaCl will remain is solution, and you can obtain it by evaporating the water. The other method to separate naphthalene and NaCl is based on sublimation property of naphthalene: you can permit that naphthalene sublimes freely or use vacuum to accelerate the process. You use a closed vessel to catch all the gas, while the NaCl will remain solid.

3 0

4 years ago