Free Reaction Kinetics MCQs with Answers
573 Reaction Kinetics MCQs from Chemistry, each with the correct answer and a written explanation of why it is correct. Free and unlimited, with no account needed.
Reaction kinetics relates reaction rate to concentration, temperature, surface area and catalysts. Questions cover rate laws, reaction order, rate constants, activation energy and the activated complex, including how a catalyst lowers the activation energy without changing the overall energy change or equilibrium position.
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573 questions · page 6 of 29
- A. >0
- B. <0
- C. Equal to 0
- D. Unpredictable
Explanation: n a reversible process, the system and its surroundings can spontaneously interconvert between two states.
Correct answer: Equal to 0- A. 1.5
- B. 3
- C. 3.5
- D. 5
Explanation: The balancing process involves adjusting the stoichiometric coefficients (numbers in front of each chemical formula) to ensure that the…
Correct answer: 3- A. 7
- B. 9.26
- C. 14
- D. zero
Explanation: The relationship between pKa and pKb of a conjugate acid-base pair is governed by the equation:pKa + pKb = 14Reasoning:CH3COOH is a weak…
Correct answer: 9.26- A. pKa
- B. pKa + pKb
- C. pKb
- D. pKa-pKb
Explanation: A buffer solution resists changes in pH when small amounts of acid or base are added.
Correct answer: pKa- A. -1
- B. 1
- C. +3
- D. +5
Explanation: Oxidation state of calcium (Ca): Calcium is a group 2 element and typically loses two electrons to form a +2 cation.
Correct answer: +5- A. Oxidation of Cu
- B. Reduction of Cu
- C. Oxidation of Ag
- D. Formation of Ag-Cu alloy
Explanation: When a copper wire is dipped in a silver nitrate (AgNO3) solution, a displacement reaction occurs.
Correct answer: Reduction of Cu- A. NH4+
- B. H+
- C. NO3-
- D. N2
Explanation: In a redox reaction, a reducing agent loses electrons and increases its oxidation state.
Correct answer: NH4+- A. Cu+2+ Mg → Cu + Mg+2
- B. Fe+2+ Cu → Fe+ Cu+2
- C. 2H++ Cu → H2+ Cu+2
- D. Mg+2+ Zn→ Mg + Zn+2
Explanation: To predict which reaction is most likely, we need to consider the relative tendency of metals to lose electrons, known as their electrode…
Correct answer: Fe+2+ Cu → Fe+ Cu+2- A. 0
- B. -6
- C. +6
- D. 12
Explanation: To determine the oxidation state of carbon in a molecule, consider the following:Oxygen: Oxygen typically has an oxidation state of -2…
Correct answer: 0- A. NH3 to NO
- B. N2 to NH3
- C. NH3 to NO3
- D. N-3 to N2
Explanation: The correct explanation is that option (b) represents the reduction of nitrogen.
Correct answer: N2 to NH3- A. Oxidation at anode, reduction at cathode
- B. No reaction at anode, reduction at cathode
- C. Reduction at anode, oxidation at cathode
- D. No reaction at cathode, reduction at anode
Explanation: In the electrolysis of molten NaCl, the correct option states that oxidation occurs at the anode, where chloride ions (Cl-) lose electrons…
Correct answer: Oxidation at anode, reduction at cathode- A. Zero
- B. Two
- C. Unity
- D. Three
Explanation: The velocity constant (k) is defined as the rate constant in the rate equation of a reaction.
Correct answer: Unity- A. 1
- B. 3
- C. 2
- D. Zero
Explanation: When a reactant is present in large excess, its concentration remains practically constant throughout the reaction.
Correct answer: 2- A. Decrease in Ea of reaction
- B. Increase in Ea of reactants
- C. Increase in number of effective collisions
- D. Decrease in number of effective collisions
Explanation: When the temperature of a reaction increases, the kinetic energy of the molecules also increases.
Correct answer: Increase in number of effective collisions- A. Slow
- B. Exothermic
- C. Fast
- D. Both (b) and (c)
Explanation: When the energy of activation (Ea) is close to the energy of the reactants, it means that the reactant molecules require relatively little…
Correct answer: Fast- A. Collision theory
- B. Van der Waal's Equation
- C. Arrhenius Equation
- D. Kinetic Equation
Explanation: The Arrhenius equation relates the rate constant of a reaction to the temperature and activation energy of the reaction.
Correct answer: Arrhenius Equation- A. Sec-1
- B. Mole dm-3 sec -1
- C. Mole -1 dm+3 sec -1
- D. Mole -2 dm+6 sec -1
Explanation: The rate law for a first-order reaction generally takes the form:Rate = kAwhere:Rate is the change in concentration of the reactant A per…
Correct answer: Sec-1- A. 7/2
- B. 3/2
- C. -3/2
- D. Zero
Explanation: The order of a reaction is the sum of the exponents of the reactant concentrations in the rate expression.
Correct answer: 3/2- A. ½(y-x)
- B. y - 2x
- C. x - y
- D. 2(x - y)
Explanation: Reverse the second equation: NO2 + O2 -> 2NO - y kJMultiply this reversed equation by 2: 2NO2 + 2O2 -> 4NO - 2y kJAdd this resulting…
Correct answer: 2(x - y)- A. Oxidizing agent
- B. Dehydrating agent
- C. Reducing agent
- D. A catalyst
Explanation: In a redox reaction, an oxidizing agent is a substance that gains electrons and is reduced.
Correct answer: Oxidizing agent