Given that: Enthalpy of combustion of Carbon (graphite) = -393kJmol^-1 Enthalpy of combustion of carbon (II) oxide = -283 kJmol^-1

Given that:
Enthalpy of combustion of Carbon (graphite) = -393kJmol^-1
Enthalpy of combustion of carbon (II) oxide = -283 kJmol^-1

(a) Write down the thermo-chemical equations for the combustion of:

(i) Carbon (graphite)

(ii) Carbon (II) oxide


(b) Determine the enthalpy of formation of carbon (II) oxide.


(c) Draw an energy level diagram for the processes in (a) and (b) above.

(d) State two properties of Carbon (IV) Oxide that make it suitable for use in fire extinguishers.

(e) When 8.0 g of sulphur is completely burned in oxygen in a calorimeter, the heat evolved raises the temperature of 500 cm³ of water by 35 ⁰C. Calculate the heat of combustion of sulphur.

(The specific heat capacity of water =

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(a) (i)


(ii)


(b)



= -393 – (-283)= -110 kJmol^-1



(c) Energy level diagram




(d) Denser than air

-Does not support combustion

-Does not burn

(e) = 500/1000 × 4.2 × 35 = 73.5

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maurice.mutuku answered the question on August 16, 2019 at 10:51

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