Home
Class 11
CHEMISTRY
When 12.0g of carbon reacted with oxygen...

When `12.0g` of carbon reacted with oxygen to form `CO` and `CO_(2)` at `25^(@)C` and constant pressure, `75.0kcal` of heat was liberated and no carbon remained . Calculate the mass of oxygen which reacted.
`(DeltaH_(f)^(@)(CO_(2))=-95kcal mol^(-1),DeltaH_(f)^(@)(CO)=-24kcal mol^(-1))`

Text Solution

Verified by Experts

The correct Answer is:
27.49
Using the data given
`C + 1/2 O_2 to CO , Delta H = -24 k cal`
`C + O_2 toCO_2 , DeltaH = - 95 k cal`
Total mass of carbon present = 12 g = 1 mole
Let a mole forms CO and b mole forms `CO_2`
`a + b = 1`…(i)
Also heat liberated `= -75 = -95 xx a + (24 xx b)`
or `95a - 24 b = 75 ` .... (ii)
Using eqs. (i) and (ii), `b = 20/71 and a = 51/71`
`:. n_(O_2)` used ` = 20/71 xx 1/2 + 51/71 = 122/142`
or Mass of `O_2` used ` = 122/142 xx 32 = 27.49 g`.
Promotional Banner

Similar Questions

Explore conceptually related problems

When 12.0g of C reacted with oxygen to form CO and CO_(2) at 25^(@)C at constant pressure, 313.8 kJ of heat was released and no carbon remained. Calculate the mass of oxygen which reacted. Delta_(f)H^(Theta) (CO,g) =- 110.5 kJ mol^(-1) and Delta_(r)H^(Theta) (CO,g) =- 393.5 kJ mol^(-1)

When 12.0g of carbon (graphite)reacted with oxygen to form CO and CO_(2) at 25^(@)C and constant pressure, 252 kJ of heat was released and no carbon remained. If Delta H_(f)^(0)(CO,g)= -110.5 kJ mol^(-1) and Delta H_(f)^(0)(CO_(2),g)= -393.5 kJ mol^(-1) ,calculate the mass of oxygen consumed.

When 12.0 g of carbon reacted with limited quantity of oxygen, 57.5 kcal of heat was produced, calculate the number of moles of CO produced (Delta_(f)H(CO_(2))=-94.5 cal, Delta_(f)H(CO)= -21.41kcal.

Calculate the heat produced when 3.785 litre of actane (C_(8)H_(18)) reacts with oxygen to form CO & water vapour at 25^(@)C . The density of octane is 0.7025 gm/ml. enthalpy of combustion of C_(8)H_(18) is -1302.7 k Cal/mol. {:(DeltaH_(f)^(@) CO_(2)(g)=-94.05" k Cal mol"^(-1),,,DeltaH_(f)^(@) CO(g)=-26.41" k Cal mol"^(-1),),(DeltaH_(f)^(@) H_(2)O(l)=-68.32" k Cal mol"^(-1),,,DeltaH_(f)^(@) H_(2)O (g)=-57.79" k Cal mol"^(-1)):}

Calculate the heat required to make 6.4kg of CaC_2 from CaO(s) and C(s) from the reaction that DeltaH_f^@(CaO) = -151.6 kcal DeltaH_f^@(CaC_2) = -14.2 kcal DeltaH_f^@(CO) = -26.4 kcal .

When 12.0g of C reacted with a limited quantity of oxygen, 57.5 kcal of heat was produced. Calculate the number of CO and number of moles of CO_(2) produced. Given C +O_(2) rarr CO_(2), Delta_(f)H = - 94.05 kcal C +1//2O_(2) rarr CO, Delta_(f)H =- 26.41 kcal