My Learning Cart
?
Categories
Account

If the rate constant of a reaction doubles when the temperature increases by 10°

₹0.0
Login to Download
  • 📥 Instant PDF Download
  • ♾ Lifetime Access
  • 🛡 Secure & Original Content

What’s inside this PDF?

Question: If the rate constant of a reaction doubles when the temperature increases by 10°C, what is the approximate activation energy (Ea) of the reaction?

Options:

  1. 20 kJ/mol
  2. 40 kJ/mol
  3. 60 kJ/mol
  4. 80 kJ/mol

Correct Answer: 40 kJ/mol

Solution: 

Using the Arrhenius equation, a doubling of the rate constant corresponds to an activation energy of approximately 40 kJ/mol for a 10°C increase.

If the rate constant of a reaction doubles when the temperature increases by 10°

Practice Questions

Q1
If the rate constant of a reaction doubles when the temperature increases by 10°C, what is the approximate activation energy (Ea) of the reaction?
  1. 20 kJ/mol
  2. 40 kJ/mol
  3. 60 kJ/mol
  4. 80 kJ/mol

Questions & Step-by-Step Solutions

If the rate constant of a reaction doubles when the temperature increases by 10°C, what is the approximate activation energy (Ea) of the reaction?
  • Step 1: Understand that the rate constant (k) of a reaction increases with temperature.
  • Step 2: Know that the Arrhenius equation relates the rate constant to temperature and activation energy: k = A * e^(-Ea/(RT)), where A is the pre-exponential factor, Ea is the activation energy, R is the gas constant, and T is the temperature in Kelvin.
  • Step 3: Recognize that if the rate constant doubles (k2 = 2 * k1) when the temperature increases by 10°C, we can use this information to find the activation energy.
  • Step 4: Use the fact that a doubling of the rate constant can be approximated using the equation: ln(k2/k1) = (Ea/R) * (1/T1 - 1/T2). Since T2 is T1 + 10°C, convert this to Kelvin (10°C = 10 + 273.15 = 283.15 K).
  • Step 5: Simplify the equation for a small temperature change (10°C) to find that Ea is approximately 40 kJ/mol.
  • Step 6: Conclude that the activation energy (Ea) of the reaction is approximately 40 kJ/mol.
  • Arrhenius Equation – The Arrhenius equation relates the rate constant of a reaction to temperature and activation energy, showing how changes in temperature affect reaction rates.
  • Activation Energy (Ea) – The minimum energy required for a reaction to occur, which can be estimated from the temperature dependence of the rate constant.
  • Temperature Dependence of Reaction Rates – Understanding how reaction rates change with temperature, particularly the concept that a small increase in temperature can significantly affect the rate constant.
Soulshift Feedback ×

On a scale of 0–10, how likely are you to recommend The Soulshift Academy?

Not likely Very likely
Home Practice Performance eBooks