Question 1: Define specific heat capacity and explain its significance in heat transfer.

Answer: Specific heat capacity is the amount of heat energy required to raise the temperature of one gram of a substance by one degree Celsius. It indicates how much heat a material can store before its temperature increases.

Question 1: Name the SI unit for specific heat capacity.

Answer: Joules per gram per degree Celsius (J/g°C)

Question 2: Describe how different materials can have different specific heat capacities.

Answer: Materials have different molecular structures and densities, which affect how much heat they can store. For example, water has a high specific heat capacity because of its hydrogen bonds, while metals like aluminum have a low specific heat capacity.

Question 1: A 200 g piece of copper is heated from 25°C to 75°C. The specific heat capacity of copper is 0.385 J/g°C. How much heat energy is required?

Answer: Q = 200 g × 0.385 J/g°C × (75°C - 25°C) = 200 × 0.385 × 50 = 3850 Joules

Question 2: A block of aluminum with a mass of 150 grams absorbs 3000 Joules of heat energy. If its temperature increases by 10°C, what is the specific heat capacity of aluminum?

Answer: c = Q / (m × ΔT) = 3000 J / (150 g × 10°C) = 3000 / 1500 = 2 J/g°C

Question 1: Describe a simple experiment to measure the specific heat capacity of a metal rod. Include variables to control and safety precautions.

Answer: The experiment involves heating a metal rod of known mass in a controlled environment, then measuring its initial and final temperatures with a thermometer. The heat energy supplied can be calculated from the power and time of heating. Variables to control include the initial temperature, ambient temperature, and power supplied. Safety precautions include wearing protective gloves and goggles, handling hot equipment carefully, and ensuring proper ventilation.

Question 1: A scientist heats 500 g of water and 500 g of sulfur from 20°C to 80°C. The heat energy supplied to each is 20,000 Joules. Which substance has a higher specific heat capacity? Justify your answer.

Answer: Water has a higher specific heat capacity because it requires more heat energy per gram to raise its temperature compared to sulfur. Since both absorb the same energy and have the same mass, the substance with the smaller temperature increase (not given here) would have the higher specific heat. However, generally, water's specific heat capacity (~4.18 J/g°C) is higher than sulfur's (~0.71 J/g°C).

Question 1: Explain why metals generally have lower specific heat capacities than water. Discuss the molecular reasons and implications for heating objects made of metal versus water.

Answer: Metals have low specific heat capacities because their atoms are tightly packed and free electrons allow rapid transfer of heat energy, resulting in quick temperature increases. Water's molecules are hydrogen-bonded, requiring more energy to increase their motion, leading to higher specific heat capacity. This means metals heat up and cool down faster than water, affecting their use in heat transfer applications and temperature regulation.

Question 1: Identify a real-world example where specific heat capacity plays a crucial role, and explain its importance.

Answer: In climate regulation, water's high specific heat capacity helps moderate Earth's temperature by absorbing and releasing heat slowly. This is crucial for maintaining stable weather patterns and supporting marine life.