You visited us 6 times! Enjoying our articles? Unlock Full Access!

Byju's Answer

Standard XII

Chemistry

Enthalpy of Combustion

When 0.36 g o...

Question

When 0.36 g of glucose was burned in a bomb calorimeter (Heat capacity $600 J K^{- 1}$ ) the temperature rise by 10 K. Calculate the standard molar enthalpy of combustion (MJ/mole).

Open in App

Solution

$M o l e s o f s u b s t a n c e = \frac{g i v e n m a s s}{M o l a r m a s s}$

$M o l e s o f g l u c o s e = \frac{0.36}{180} = 0.002 m o l e s$
$M o l a r e n t h a l p y o f c o m b u s t i o n = \frac{h e a t c a p a c i t y \times r i s e i n t e m p e r a t u r e}{m o l e s o f g l u c o s e}$
$M o l a r e n t h a l p y o f c o m b u s t i o n = \frac{600 \times 10}{0.002} = 3 \times 10^{6} J / m o l = 3 M J / m o l$

Suggest Corrections

Similar questions

Q. When

1.0 g

of oxalic acid

(H_{2} C_{2} O_{4})

is burned in a bomb calorimeter whose heat capacity is

8.75 k J / K

, the temperature increases by

0.312 K

. The enthalpy of combustion of oxalic acid at

27^{o} C

is:

Q. A sample of

0.16 g C H_{4}

was subjected to the combustion at

27^{o} C

in a bomb calorimeter. The temperature of the calorimeter. The temperature of the calorimeter system (including water) was found to rise by

{0.5}^{o} C

. Calculate the heat of combustion of methane at
(i) constant volume and
(ii) constant pressure. the thermal capacity of calorimeter system is

17.0 k J K^{- 1}

and

R = 8.314 J K^{- 1} m o l^{- 1}

Q. When

1.0 g

of fructose

C_{6} H_{12} O_{6} (s)

is burned in oxygen in a bomb calorimeter, the temperature of the calorimeter water increases by

{1.56}^{o} C

. If the heat capacity of the calorimeter and its contents is

10.0 k J /^{o} C

. Calculate the enthalpy of combustion of fructose at

298 K

When $1.0 g$ of oxalic acid ( $H_{2} C_{2} O_{4})$ is burned in a bomb calorimeter whose heat capacity is $8.75 k J / K$ , the temperature increased by $0.312 K$ . The enthalpy of combustion of oxalic acid at $27^{\circ} C$ .

Q. A

1.250 g

sample of octane

(C_{8} H_{18})

is burned in excess of oxygen in a bomb calorimeter. The temperature of calorimeter rises from

294.05 K

300.78 K

. If heat capacity of calorimeter and its contents is

8.93 k J / K

, calculate the heat transferred to calorimeter.

Join BYJU'S Learning Program

When 0.36 g of glucose was burned in a bomb calorimeter (Heat capacity 600JK−1) the temperature rise by 10 K. Calculate the standard molar enthalpy of combustion (MJ/mole).

Moles of substance=given massMolar massMoles of glucose=0.36180=0.002 molesMolar enthalpy of combustion=heat capacity×rise in temperaturemoles of glucoseMolar enthalpy of combustion=600×100.002=3×106 J/mol=3 MJ/mol

When 0.36 g of glucose was burned in a bomb calorimeter (Heat capacity $600 J K^{- 1}$ ) the temperature rise by 10 K. Calculate the standard molar enthalpy of combustion (MJ/mole).