HARD
JEE Main
IMPORTANT
Earn 100

In order to get maximum calorific output, a burner should have an optimum fuel-to-oxygen ratio which corresponds to 3 times as much oxygen as is required theoretically for complete combustion of the fuel. A burner which has been adjusted for methane as fuel (with X litre hour-1 of CH4 and 6X litre hour-1 of O2) is to be readjusted for butane, C4H10. In order to get the same calorific output, what should be the rate of supply of butane and oxygen? Assume that losses due to incomplete combustion, etc, are the same for both fuels and that the gases behave ideally. Heat of combustion: CH4=809 kJ mole-1, C4H10=2878 kJ mole-1.

Important Questions on Miscellaneous Problems for Revision

MEDIUM
JEE Main
IMPORTANT

0.16 g of methane was subjected to combustion at 27°C in a bomb calorimeter. The temperature of the calorimeter system (including water) was found to rise by 0.5°C. Calculate the heat of combustion of methane in terms of kJ mol-1 at constant volume with a proper sign either +/-.

[Given: The thermal capacity of the calorimeter system is 17.7 kJ K1, R=8.314 J mol1K1]

MEDIUM
JEE Main
IMPORTANT

0.16 g of methane was subjected to combustion at 27°C in a bomb calorimeter. The temperature of the calorimeter system (including water) was found to rise by 0.5°C. Calculate the heat of combustion of methane in terms of kJ mol-1 at constant pressure with a proper sign either +/- and please correct up to three decimal places. The thermal capacity of the calorimeter system is 17.7 kJ K-1· R=8.31 J K-1 mol-1.

HARD
JEE Main
IMPORTANT
The rates of effusion of two gases A and B under the same conditions of temperature and pressure are in the ratio YA: YB=2:1. The ratio of the root-mean-square (rms) speeds of molecules of A and B, will be (x:2) if TA:TB=2:1? Find the value of x.
MEDIUM
JEE Main
IMPORTANT
There were 201 rows of spectators sitting in a hall. A magician releases laughing gas N2O from the front and tear gas molecular weight=176 from the rear of the hall, simultaneously. Which row of spectators from the front will have the tendency to smile and weep simultaneously?
MEDIUM
JEE Main
IMPORTANT

At what temperature (in Kelvin) does the average translational kinetic energy of a molecule in a gas becomes equal to the kinetic energy of an electron accelerated from rest through a potential difference of 1 volt? Answer has to be rounded-off to the nearest integer.

1 eV=1.602×10-12 erg, k=1.38×10-23 m2 kg s-2 K-1

MEDIUM
JEE Main
IMPORTANT

The Kp value for the reaction equilibrium: H2(g)+I2(g)2HI(g) is 871 at 25°C. If the vapour pressure of iodine is 4×10-4 atm, The equilibrium constant in terms of partial pressures is x × 10-2 at the same temperature for the reaction equilibrium H2(g)+I2(s)2HI(g) . The value of x should be given to the nearest interger value.

MEDIUM
JEE Main
IMPORTANT

Solid NH4HS is taken in an evacuated vessel and allowed to dissociate at a certain temperature until the total gas pressure is 0.66 atm. What would be the value of Kp for the following reaction?

NH4HS(s)NH3(g)+H2S(g)

What would be the partial pressure of H2S, if additional NH3 is introduced into the equilibrium mixture at the same temperature, until the partial pressure of NH3 is 0.921 atm? (Answer to be rounded up to three places of decimals)

MEDIUM
JEE Main
IMPORTANT

Solid ammonium carbamate, NH2COONH4, dissociates on heating to NH3 and CO2.

NH2COONH4(s)2NH3(g)+CO2(g)

When pure carbamate is put into a closed container and allowed to attain equilibrium with the gaseous products at a constant temperature, 35°C, the total pressure is found to be 0.30 atm. Determine Kp in 10-3 atm3 for this reaction at 35°C.