Domanda del libro di testo
Use standard enthalpies of formation to calculate the standard change in enthalpy for the melting of ice. (The ΔH°f for H2O(s) is –291.8 kJ/mol.)
1855
views
Ch.7 - Thermochemistry
Tro5th EditionChemistry: A Molecular ApproachISBN: 9780134874371
Non è quello che usi tu?Cambia libro di testoScegli un libro di testo diverso
TOC.tableOfContents
- Ch.1 - Matter, Measurement & Problem Solving117
- Ch.2 - Atoms & Elements106
- Ch.3 - Molecules and Compounds128
- Ch.4 - Chemical Reactions and Chemical Quantities56
- Ch.5 - Introduction to Solutions and Aqueous Solutions84
- Ch.6 - Gases112
- Ch.7 - Thermochemistry96
- Ch.8 - The Quantum-Mechanical Model of the Atom60
- Ch.9 - Periodic Properties of the Elements86
- Ch.10 - Chemical Bonding I: The Lewis Model91
- Ch.11 - Chemical Bonding II: Molecular Shapes, VSEPR & MO Theory85
- Ch.12 - Liquids, Solids & Intermolecular Forces51
- Ch.13 - Solids & Modern Materials48
- Ch.14 - Solutions93
- Ch.15 - Chemical Kinetics114
- Ch.16 - Chemical Equilibrium68
- Ch.17 - Acids and Bases137
- Ch.18 - Aqueous Ionic Equilibrium154
- Ch.19 - Free Energy & Thermodynamics91
- Ch.20 - Electrochemistry105
- Ch.21 - Radioactivity & Nuclear Chemistry74
- Ch.22 - Organic Chemistry141
Tro5th EditionChemistry: A Molecular ApproachISBN: 9780134874371Non è quello che usi tu?Cambia libro di testo
Capitolo 7, Problema 97b
The kinetic energy of a rolling billiard ball is given by KE = 1/2 mv2. Suppose a 0.17-kg billiard ball is rolling down a pool table with an initial speed of 4.5 m/s. As it travels, it loses some of its energy as heat. The ball slows down to 3.8 m/s and then collides head-on with a second billiard ball of equal mass. The first billiard ball completely stops and the second one rolls away with a velocity of 3.8 m/s. Assume the first billiard ball is the system. Calculate q.
Guida verificata passo dopo passo1
Identify the initial kinetic energy (KE_initial) of the first billiard ball using the formula KE = \(\frac{1}{2}\)mv^2, where m is the mass and v is the initial velocity.
Calculate the initial kinetic energy: KE_initial = \(\frac{1}{2}\) \(\times\) 0.17 \(\text{ kg}\) \(\times\) (4.5 \(\text{ m/s}\))^2.
Identify the final kinetic energy (KE_final) of the first billiard ball just before the collision using the same formula with the final velocity.
Calculate the final kinetic energy: KE_final = \(\frac{1}{2}\) \(\times\) 0.17 \(\text{ kg}\) \(\times\) (3.8 \(\text{ m/s}\))^2.
Determine the heat lost (q) by the system, which is the difference between the initial and final kinetic energies: q = KE_initial - KE_final.
Risposta video verificata per un problema simile:
Questa soluzione video è stata consigliata dai nostri tutor come utile per risolvere questo problema.
Durata del video:
4mConcetti chiave
Ecco i concetti essenziali che devi comprendere per rispondere correttamente alla domanda.
Kinetic Energy
Kinetic energy (KE) is the energy an object possesses due to its motion, calculated using the formula KE = 1/2 mv², where m is the mass and v is the velocity of the object. In this scenario, the billiard ball's kinetic energy changes as it slows down and eventually transfers its energy during a collision.
Video consigliato:
Percorso guidato
00:34
Kinetic & Potential Energy
Conservation of Momentum
The principle of conservation of momentum states that in a closed system, the total momentum before an event must equal the total momentum after the event. In this case, the momentum of the first billiard ball is transferred to the second ball during the collision, allowing us to analyze the system's behavior before and after the impact.
Video consigliato:
Percorso guidato
01:48Law of Conservation of Mass
Heat Transfer (q)
Heat transfer, denoted as q, refers to the energy that is transferred from one system to another due to a temperature difference. In this problem, as the first billiard ball slows down, some of its kinetic energy is converted into heat, which can be quantified to understand the energy lost during its motion.
Video consigliato:
Percorso guidato
00:44Heat Capacity
Pratica correlata
Domanda del libro di testo
In a sunny location, sunlight has a power density of about 1 kW/m2. Photovoltaic solar cells can convert this power into electricity with 15% efficiency. If a typical home uses 385 kWh of electricity per month, how many square meters of solar cells are required to meet its energy requirements? Assume that electricity can be generated from the sunlight for 8 hours per day.
685
views
Domanda del libro di testo
LP gas burns according to the exothermic reaction: C3H8(g) + 5 O2(g) → 3 CO2(g) + 4 H2O(g) ΔH°rxn = –2044 kJ What mass of LP gas is necessary to heat 1.5 L of water from room temperature (25.0 °C) to boiling (100.0 °C)? Assume that during heating, 15% of the heat emitted by the LP gas combustion goes to heat the water. The rest is lost as heat to the surroundings.
2175
views
1
rank
Domanda del libro di testo
Methanol (CH3OH) has been suggested as a fuel to replace gasoline. Find ΔH°rxn, and determine the mass of carbon dioxide emitted per kJ of heat produced. Use the information from the previous exercise to calculate the same quantity for octane, C8H18. How does methanol compare to octane with respect to global warming?
1193
views