81- The unit of Kc for the system PCl₅ = PCl₃ + Cl₂ is?
A. dm³/mol
B. mol/dm³
C. mol/dm⁶
D. mol²/dm⁶
View Answer
Answer : B. mol/dm³
Description
82- For a first order reaction A → B, the rate constant is 0.0458 s⁻¹. Calculate rate of the reaction if the concentration of reactant is 0.35mol dm⁻³.
A. 0.012 mol dm⁻³ s⁻¹
B. 0.014 mol dm⁻³ s⁻¹
C. 0.016 mol dm⁻³ s⁻¹
D. 0.018 mol dm⁻³ s⁻¹
View Answer
Answer : C. 0.016 mol dm⁻³ s⁻¹
Description
83- A reaction is first order with respect to A and second order with respect to B, the rate equation is?
A. Rate = k [A]
B. Rate = k [A][B]
C. Rate = k [A]²[B]
D. Rate = k [A][B]²
View Answer
Answer : D. Rate = k [A][B]²
Description
84- What mass of aluminium oxide (Al₂O₃) is produced from 18.5g of Al metal, when it reacts completely with oxygen gas according to the following equation?
4Al(s) + 3O₂(g) → 2Al₂O₃(s)
A. 30.8g
B. 32.6g
C. 34.9g
D. 36.5g
View Answer
Answer : C. 34.9g
Description
85- Calculate the work done when 1 mole of an ideal gas expands from 15 dm³ to 20 dm³ against a constant external pressure of 2 atmospheres.
A. -10 atm.dm³
B. -5 atm.dm³
C. 5 atm.dm³
D. 10 atm.dm³
View Answer
Answer : A. -10 atm.dm³
Description
86- When 1 mole of ice melts at 0°C and constant pressure of 1 atmosphere, 6025 J of heat is absorbed by the system. The molar volume of ice and water are 0.020 and 0.018 dm³, respectively. Calculate ΔE.
(1dm³.atm=101.33J)
A. 6010.20J
B. 6015.20J
C. 6020.20J
D. 6025.20J
View Answer
Answer : A. 6010.20J
Description
87- One slice of bread with a tablespoon of peanut butter on it contains 20g carbohydrate, 10g protein, and 9g fat. Calculate total energy consumed in this intake.
A. 158kcal
B. 173kcal
C. 201kcal
D. 218kcal
View Answer
Answer : C. 201kcal
Description
88- ΔH can be measured indirectly by applying?
A. Avogadro’s law
B. Faraday’s law
C. Gas’s law
D. Hess’s law
View Answer
Answer : D. Hess’s law
Description
89- The heat of sublimation of potassium is 98kJ/mol, the heat of dissociation of bromine gas is 192.5 kJ/mol. The ionization energy of K is 414 kJ/mol. The electron affinity of Br is -334.7 kJ/mol and the heat of formation of KBr is -405.8 kJ/mol. Calculate the lattice energy of KBr.
A. -679.3
B. -669.5
C. 669.5
D. 679.3
View Answer
Answer : D. 679.3
Description
90- Which one of the following is a strong electrolyte in solution?
A. Acetic acid
B. Ammonium hydroxide
C. Carbonic acid
D. Potassium iodide
View Answer
Answer : D. Potassium iodide
Description
91- When 4 g of magnesium was heated in excess of oxygen. Calculate the theoretical yield of magnesium oxide (MgO).
A. 3.7g
B. 4.2g
C. 5.4g
D. 6.6g
View Answer
Answer : D. 6.6g
Description
92- The electrode potential of the standard hydrogen electrode is chosen as:
A. -1 V
B. 0 V
C. 1 V
D. 2 V
View Answer
Answer : B. 0 V
Description
93- Electromegativity of Al is approximately equal to that of?
A. B
B. Be
C. Mg
D. Na
View Answer
Answer : B. Be
Description
94- Which of the following alkali metal forms only normal oxide with O₂?
A. K
B. Li
C. Na
D. Rb
View Answer
Answer : B. Li
Description
95- Third period element that initially reacts rapidly with oxygen to form a protective oxide coating that prevents further reactions is:
A. Al
B. Mg
C. Na
D. Si
View Answer
Answer : A. Al
Description
96- Cu²⁺ salt solution is blue in colour due to transition of electrons from?
A. d to d orbital
B. p to d orbital
C. p to p orbital
D. s to p orbital
View Answer
Answer : A. d to d orbital
Description
97- Potassium ferrocyanide is which type of salt?
A. Complex
B. Double
C. Mixed
D. Normal
View Answer
Answer : A. Complex
Description
98- Name of ketone functional group is?
A. Amino
B. Carbonyl
C. Carboxyl
D. Formyl
View Answer
Answer : B. Carbonyl
Description
99- Pyridine belongs to which class of organic compounds?
A. Alicyclic
B. Heterocyclic
C. Homocyclic
D. Hydrocarbon
View Answer
Answer : B. Heterocyclic
Description
100- Which of the following elements cannot be detected directly in a given organic compound?
