201. If 1.5 moles of oxygen combines with aluminium to form Al2O₃, then the weight of aluminium (atomic weight = 27 ) used in this reaction is __________ gm.
27
54
5.4
2.7
✅ The correct answer is option B.
Statiometery MCQs
202. Hess’s law of constant heat summation is based on conservation of mass. It deals with
Equilibrium constant
Reaction rate
Changes in heat of reaction
None of these
✅ The correct answer is option C.
203. The value of gas constant ‘R’ is __________ kcal/kg.mole.°C.
2.79
1.987
3.99
None of these
✅ The correct answer is option D.
204. Heat of neutralisation of a strong acid and strong base is always a constant value, i.e., 57 KJ/Kg mole. This is because
The strong base and strong acid reacts completely
The salt formed does not hydrolyse
Only OH⁻ and H⁺ ions react in every case
The strong base and strong acid reacts in aqueous solution
✅ The correct answer is option C.
205. A chemical process is said to occur under unsteady state, if the
Inventory changes do not take place
Ratio of streams entering/leaving are independent of time
Flow rates & composition both are time dependent
None of these
✅ The correct answer is option C.
206. Avogadro number is the number of molecules in one __________ of a gas.
Gram
Kilogram
Gm.mole
Litre
✅ The correct answer is option C.
207. The ratio of existing moles of vapor per mole of vapor free gas to the moles of vapor that would be present per mole of vapor free gas, if the mixture were saturated at the existing temperature & pressure, is termed as the
Relative humidity
Relative saturation
Percentage saturation
None of these
✅ The correct answer is option C.
208. Boiling point of a non-homogeneous mixture of immiscible liquids is __________ that of any one of its separate components.
Lower than
Higher than
Equal to
Either A or B; depends on the liquids
✅ The correct answer is option A.
209. A car tyre of volume 0.057 m³ is inflated to 300 kPa at 300 K. After the car is driven for 10 hours, the pressure in the tyre increases to 330 kPa. Assume air is an ideal gas and Cv for air is 21 J/mole.K. The change in the internal energy of air in the tyre in J/mole is
380
630
760
880
✅ The correct answer is option B.
210. Pick out the wrong unit conversion of thermal conductivity.
1 BTU/ft².hr.°F/ft = 1.488 kcal/m². hr.°C/m
1 BTU/ft².hr.°F/inch = 1.488 kcal/m². hr.°C/m
1 kcal/m.hr.°C = 0.672 BTU/ft.hr.°F = 1.163 W/m. °K
1 W/cm.°C = 85.985 kcal/m.hr.°C = 57.779 BTU/ft.hr.°F
✅ The correct answer is option B.