Question 1: Define the term 'reaction rate' in the context of chemistry.

Answer: Reaction rate is the speed at which reactants are converted into products in a chemical reaction, typically expressed as change in concentration over time.

Question 2: Explain how an increase in temperature generally affects the collision frequency and energy of particles in a reaction.

Answer: Increasing temperature increases the collision frequency and the energy of particles, leading to more frequent and more energetic collisions, which speeds up the reaction.

Question 3: What is the collision theory, and how does temperature influence it?

Answer: Collision theory states that particles must collide with sufficient energy and proper orientation for a reaction to occur. Higher temperatures increase particle energy and collision frequency, thus increasing the likelihood of successful reactions.

Question 4: Identify two safety precautions that should be taken when conducting experiments involving high temperatures.

Answer: Wearing heat-resistant gloves and safety goggles, and ensuring proper ventilation are essential safety precautions.

Question 5: Fill in the blank: According to the Arrhenius equation, as the temperature increases, the rate constant (k) ___, assuming other factors remain constant.

Answer: increases

Question 1: Calculate the change in reaction rate if the temperature increases from 25°C to 35°C, given that the rate doubles for every 10°C increase. Show your calculations.

Answer: The rate doubles for every 10°C increase. Therefore, from 25°C to 35°C (a 10°C increase), the rate doubles. Answer: Rate increases by a factor of 2.

Question 2: Using the Arrhenius equation, if the rate constant k at 20°C is 0.05 s⁻¹, estimate the rate constant at 30°C, assuming the activation energy (Ea) is 50 kJ/mol. (Use R = 8.314 J/mol·K).

Answer: Using Arrhenius equation: ln(k2/k1) = (Ea/R) * (1/T1 - 1/T2) Convert temperatures to Kelvin: T1=293K, T2=303K. ln(k2/0.05) = (50000/8.314) * (1/293 - 1/303) Calculate: ln(k2/0.05) ≈ (6014.66) * (0.003413 - 0.003300) ≈ 6014.66 * 0.000113 ≈ 0.680 k2 = 0.05 * e^{0.680} ≈ 0.05 * 1.974 ≈ 0.0987 s⁻¹ Answer: approximately 0.099 s⁻¹.

Question 1: Describe a simple experiment to demonstrate the effect of temperature on reaction rate, including variables to control and safety considerations.

Answer: One simple experiment involves reacting sodium thiosulfate with hydrochloric acid at different temperatures. Variables to control include concentration and volume of reactants, while temperature is varied using water baths. Safety considerations include wearing goggles, gloves, and handling acids carefully to prevent spills and burns.

Question 2: How do industries utilize the principle that increasing temperature speeds up reactions, for example in manufacturing or energy production?

Answer: Industries use higher temperatures to accelerate chemical reactions in processes like steelmaking, catalytic cracking in oil refineries, and power generation in thermal plants, improving efficiency and productivity.

Question 3: Explain why it is important to control temperature carefully in chemical manufacturing processes.

Answer: Controlling temperature ensures reactions proceed at the desired rate, maintains product quality, prevents hazardous situations, and optimizes energy use and safety.