Question 1: Explain briefly how increasing the temperature affects the rate of a chemical reaction.

Answer: Increasing temperature generally increases the reaction rate because particles move faster and collide more frequently and with greater energy.

Question 1: Define activation energy in the context of chemical reactions.

Answer: Activation energy is the minimum amount of energy required for reactants to undergo a successful collision resulting in a reaction.

Question 2: Describe how temperature influences the kinetic energy of particles involved in a reaction.

Answer: Higher temperature increases the kinetic energy of particles, causing them to move faster and collide more effectively.

Question 1: The rate constant (k) for a reaction at 300 K is 0.02 s⁻¹. If the temperature increases to 330 K, and the activation energy (Ea) is 50 kJ/mol, calculate the new rate constant using the Arrhenius equation: k = A * e^(-Ea/RT). Assume A remains constant. (Use R = 8.314 J/mol·K).

Answer: k₂ = 0.055 s⁻¹ (approximately)

Question 2: A reaction's rate doubles when the temperature increases from 298 K to 308 K. What is the approximate activation energy (Ea) for this reaction? (Use the relation: Rate2 / Rate1 = e^{(Ea/R) * (1/T1 - 1/T2)}).

Answer: Ea ≈ 52 kJ/mol

Question 1: Describe a simple experiment you could perform to observe the effect of temperature on reaction rate. Include the variables you would control and safety precautions.

Answer: One experiment involves reacting sodium thiosulfate with hydrochloric acid at different temperatures. Control variables include concentration and volume, while temperature is varied using a water bath. Safety precautions include wearing goggles and gloves, handling acids carefully, and ensuring proper disposal of chemicals.

Question 1: A reaction was performed at three different temperatures: 290 K, 310 K, and 330 K. The observed reaction times decreased from 120 seconds at 290 K to 60 seconds at 310 K, and 30 seconds at 330 K. Explain how temperature influences the reaction rate based on this data.

Answer: As temperature increases, the reaction rate increases, evidenced by the decreasing reaction times. Higher temperatures cause particles to collide more frequently and with greater energy, resulting in faster reactions.

Question 1: Explain why increasing temperature generally increases the rate of a chemical reaction, including the role of activation energy and particle collisions. (6 marks)

Answer: Increasing temperature raises the kinetic energy of particles, leading to more particles having enough energy to overcome the activation energy barrier. This results in more successful collisions per unit time, thereby increasing the reaction rate.

Question 1: Describe how understanding the effect of temperature on reaction rates is important in industrial processes such as manufacturing pharmaceuticals or food preservation.

Answer: In industry, controlling temperature optimizes reaction speed and product quality. For example, higher temperatures can speed up pharmaceutical synthesis, but must be balanced with safety and product stability. In food preservation, lower temperatures slow microbial growth, extending shelf life.