1. A bottle of juice at room temperature is placed in a bucket of ice inside a box. The box, bottle, and bucket of ice represent a closed system. Which of the following statements is true? (2.0 points) (Points : 2)
Heat flows from the ice to the juice while the total energy of the system remains the same.
Heat flows from the juice to the ice while the total energy of the system increases.
Heat flows from the ice to the juice while the total energy of the system decreases.
Heat flows from the juice to the ice while the total energy of the system remains the same.
2. The standard enthalpy for a reaction is -598 kJ/mol. The reaction can be described as: (2.0 points) (Points : 2)
exothermic, releasing energy into the environment.
endothermic, releasing energy into the environment.
exothermic, absorbing energy from the environment.
endothermic, absorbing energy from the environment.
3. What is the difference between heat and temperature? (2.0 points) (Points : 2)
Heat is thermal energy, while temperature is the measurement of average kinetic energy of the particles of matter.
Temperature is thermal energy, while heat is the measurement of average kinetic energy of the particles of matter.
Temperature measures thermal energy, while heat measures molecular energy.
There is no difference between heat and temperature.
4. When a student reacts phosphoric acid and water, she notices that the container feels warm. What makes the container feel warm? (2.0 points) (Points : 2)
The reaction is exothermic and gives off heat energy.
The reaction is exothermic and absorbs heat energy.
The reaction is endothermic and gives off heat energy.
The reaction is endothermic and absorbs heat energy.
5. What is meant by entropy? (1.0 points) (Points : 1)
Heat of formation
Temperature of condensation
Degree of randomness and disorder
The absolute temperature of evaporation
1. The correct statement is: "Heat flows from the ice to the juice while the total energy of the system remains the same."
To determine how heat flows in this closed system, we need to understand the principles of thermodynamics. In this scenario, the bottle of juice is at room temperature, while the bucket of ice is at a lower temperature. According to the second law of thermodynamics, heat flows from a higher temperature region to a lower temperature region. Therefore, the heat flows from the ice to the juice.
As for the total energy of the system, it remains the same because energy is conserved in a closed system. The heat lost by the ice is gained by the juice, resulting in no net change in the total energy of the system.
2. The correct description of the reaction is: "exothermic, releasing energy into the environment."
The standard enthalpy of a reaction is a measure of the heat energy change accompanying the reaction. A negative value for the standard enthalpy indicates an exothermic reaction, meaning that energy is released into the environment.
3. The correct difference between heat and temperature is: "Heat is thermal energy, while temperature is the measurement of average kinetic energy of the particles of matter."
Heat refers to the transfer of thermal energy from one object to another due to a temperature difference. It is a form of energy transfer. On the other hand, temperature is a measure of the average kinetic energy of the particles in a substance. It gives us an indication of how hot or cold an object or substance is.
4. The reason the container feels warm is: "The reaction is exothermic and gives off heat energy."
An exothermic reaction is one that releases heat energy to the surroundings. In this case, the reaction between phosphoric acid and water results in the release of heat energy. This heat energy is transferred to the surrounding container, causing it to feel warm.
5. Entropy is defined as: "The degree of randomness and disorder."
Entropy is a measure of the randomness or disorder in a system. It quantifies the distribution of energy and particles within a system. A high entropy indicates a greater degree of randomness or disorder, while a low entropy indicates a more ordered system. It is a concept in thermodynamics that relates to the second law of thermodynamics, which states that the entropy of an isolated system tends to increase over time.