Heat of reaction equations

Using simultaneous equations

Simultaneous equations

GIVEN: ΔHA + B = C -50D + E = F +24F + C = H ???

Simultaneous equations

GIVEN: ΔHA + B = C -50D + E = F +24F + C = A+ B + C + D ???

Simultaneous equations

GIVEN: ΔHA + B = C -50D + E = F +24A+ B + E + D= H -26

INTERPRETING DATA

INTERPRETING DATA

INTERPRETING DATA

INTERPRETING DATA

Using this to solve an unknown reaction

2009 Q6(e) The combustion of Butene C4H8 is described by the following balanced

equation.C4H8 + 6O2 4CO2 + 4H2O

ΔH = –2710 kJ mol–1

The standard heats of formation of water and carbon dioxide are –286 and –394 kJ

mol–1, respectively.Calculate the heat of formation of C4H8

What have we been told??

2009 Q6(e) The combustion of Butene C4H8 is described by the following balanced

equation.

• C4H8 + 6O2 4CO2 + 4H2O

ΔH = –2710 kJ mol–1

This is the energy given out when butene is burned in oxygen

What have we been told??

2009 Q6(e) The combustion of one of Butene C4H8 is

described by the following balanced equation.

C4H8 + 6O2 4CO2 + 4H2OΔH = –2710 kJ mol–1

The standard heats of formation of water and carbon dioxide are –286 and –394 kJ mol–1,

respectively.Calculate the heat of formation of C4H8

What have we been told??

The standard heats of formation of water and carbon dioxide are –286

and –394 kJ mol–1, respectively.ΔH = kJ mol–1

H2 + ½O2 H2O -286

C + O2 CO2 -394

What do we need to know?

4C + 4H2 C4H8 ΔH = ???

Using all the given info one has to manipulate the given formulas to

leave the needed one.

The question seeks to answer if the formation of butene is exothermic or endothermic

What’s next?

Write down all the info you have.

ΔH = kJ mol–1

H2 + ½O2 H2O -286

C + O2 CO2 -394

C4H8 + 6O2 4CO2 + 4H2O –2710

What’s next?

Write down all the info you have.

ΔH = kJ mol–1

H2 + ½O2 H2O -286

C + O2 CO2 -394

C4H8 + 6O2 4CO2 + 4H2O –2710 4C + 4H2 C4H8 ΔH = ???

What’s next?

ΔH = kJ mol–1

H2 + ½O2 H2O -286

C + O2 CO2 -394

C4H8 + 6O2 4CO2 + 4H2O –2710 4C + 4H2 C4H8 ΔH = ???

What’s next?

ΔH = kJ mol–1

H2 + ½O2 H2O -286

C + O2 CO2 -394

C4H8 + 6O2 4CO2 + 4H2O –2710

4CO2 + 4H2O C4H8 + 6O2 2710

4C + 4H2 C4H8 ΔH = ???4C + 4H2 C4H8 ΔH = ???reverse

What’s next?

ΔH = kJ mol–1

H2 + ½O2 H2O -286

C + O2 CO2 -394

C4H8 + 6O2 4CO2 + 4H2O –2710

4CO2 + 4H2O C4H8 + 6O2 2710

4C + 4O2 4CO2 -1576

4C + 4H2 C4H8 ΔH = ???x4x4

What’s next?

ΔH = kJ mol–1

H2 + ½O2 H2O -286

C + O2 CO2 -394

C4H8 + 6O2 4CO2 + 4H2O –2710

4CO2 + 4H2O C4H8 + 6O2 2710

4C + 4O2 4CO2 -1576

4H2 + 2O2 4H2O -1144

4C + 4H2 C4H8 ΔH = ???x4x4

What’s next?

ΔH = kJ mol–1

4CO2 + 4H2O C4H8 + 6O2 2710

4C + 4O2 4CO2 -1576

4H2 + 2O2 4H2O -1144

4C + 4H2 C4H8 ΔH = ???

What’s next?

4C + 4H2 C4H8 ΔH = ???

What’s next?

4C + 4H2 C4H8 ΔH = ???

What’s next?

4C + 4H2 C4H8 ΔH = ???

What’s next?

4C + 4H2 C4H8 ΔH = ???

What’s next?

4C + 4H2 C4H8 ΔH = ???

What’s next?

4C + 4H2 C4H8 ΔH = ???

What’s next?

4C + 4H2 C4H8 ΔH = ???

What’s next?

4C + 4H2 C4H8 ΔH = ???

What’s next?

4C + 4H2 C4H8 ΔH = ???

What’s next?

4C + 4H2 C4H8 ΔH = ???

What’s next?

4C + 4H2 C4H8 ΔH = ???

What’s next?

4C + 4H2 C4H8 ΔH = ???