Physics 101 Lecture 5: Heat & Gay-Lussac's Law

To convert Celsius to Kelvin, add 273 to the Celsius temperature.

The pressure of a gas decreases as it rises to a higher altitude.

The ideal gas law is represented by the formula pV = nRT.

<p>Avogadro’s number represents the amount of molecules in one mole of a substance, approximately 6.022 × 10^23.</p> Signup and view all the answers

<p>The thermal energy is calculated using the equation Q = mc∆T.</p> Signup and view all the answers

<p>The final volume can be found using the ideal gas law equation, where pressure and temperature changes are accounted for.</p> Signup and view all the answers

<p>The initial temperature is 308 K after converting from 35.0 °C.</p> Signup and view all the answers

<p>Failure to convert temperatures to Kelvin may lead to incorrect calculations and results.</p> Signup and view all the answers

<p>The ideal gas law expresses the relationship between pressure, volume, and temperature of a gas, taking into account the number of moles.</p> Signup and view all the answers

<p>Avogadro's number is $6.022 × 10^{23}$ molecules/mole and it signifies that one mole of any gas contains the same number of molecules.</p> Signup and view all the answers

<p>In the ideal gas equation, the mass of a gas is represented in terms of the number of moles, $n$, and the universal gas constant, $R$.</p> Signup and view all the answers

<p>The ideal gas law applies when the gas behaves ideally, typically at high temperatures and low pressures.</p> Signup and view all the answers

<p>Keeping pressure constant allows for a direct calculation of the change in temperature when the volume changes.</p> Signup and view all the answers

<p>Temperature must always be expressed in Kelvin for the ideal gas equation to be valid.</p> Signup and view all the answers

<p>The universal gas constant, R, represents the proportionality factor in the ideal gas equation, connecting the gas's physical properties.</p> Signup and view all the answers

<p>If the volume of a gas is increased while keeping pressure constant, the temperature of the gas must also increase.</p> Signup and view all the answers

<p>The primary cause of a sea breeze is the descent of cool air from the sea to replace the rising hot air over the land.</p> Signup and view all the answers

<p>During a land breeze at night, cooler air from the land flows towards the warmer sea, reversing the sea breeze effect.</p> Signup and view all the answers

<p>Natural convection in a room occurs when air in contact with the radiator rises, allowing cooler air to move in and replace it, creating a cycle.</p> Signup and view all the answers

<p>Conduction is the transfer of thermal energy through molecular action without the motion of the medium, and it is most pronounced in solids.</p> Signup and view all the answers

<p>When one end of an iron bar is placed in a fire, thermal energy is conducted from the hot end to the cold end, heating the entire bar.</p> Signup and view all the answers

<p>Molecular vibrations allow atoms in the hotter part of a solid to interact with their neighbors, passing energy and causing a transfer of thermal energy.</p> Signup and view all the answers

<p>The cross-sectional area A and thickness d of a material significantly affect the amount of thermal energy conducted through it.</p> Signup and view all the answers

<p>Thermal energy flows from the hot side with temperature Th to the colder side with temperature Tc in a slab, driven by the temperature difference.</p> Signup and view all the answers

<p>The factors include the area A of the slab, the time t, and the temperature difference, $T_h - T_c$.</p> Signup and view all the answers

<p>The thermal energy transfer is inversely proportional to the thickness of the slab, meaning thicker slabs transfer less energy.</p> Signup and view all the answers

<p>The coefficient of thermal conductivity, k, quantifies how well a material conducts thermal energy.</p> Signup and view all the answers

<p>It is significant because metals facilitate efficient heat transfer, making them ideal for applications requiring thermal conductivity.</p> Signup and view all the answers

<p>The thermal energy conducted can be expressed as $Q = kA(Th - Tc)t / d$.</p> Signup and view all the answers

<p>A larger temperature difference between the faces of the slab results in a greater amount of thermal energy flowing through.</p> Signup and view all the answers

<p>If a material has a small thermal conductivity, it can be inferred that the material serves as a good insulator.</p> Signup and view all the answers

<p>A 'good conductor' implies that the material has a high thermal conductivity and allows a significant amount of thermal energy to flow.</p> Signup and view all the answers

<p>Gay-Lussac's Law states that the pressure of a gas is directly proportional to its absolute temperature when the volume is held constant.</p> Signup and view all the answers

<p>The slope, represented as m', is equal to the product of the absolute pressure (p0) and the coefficient of volume expansion (β) for the gas.</p> Signup and view all the answers

<p>The simplified equation for pressure at 0°C is p = m't + p0.</p> Signup and view all the answers

<p>The term β represents the coefficient of volume expansion for a gas, which indicates how much the volume of the gas expands per unit temperature increase.</p> Signup and view all the answers

<p>If the absolute pressure p0 is doubled, the pressure p at a given temperature t will also double, as p = p0(βt + 1).</p> Signup and view all the answers

<p>If the temperature of the gas is decreased, the pressure will also decrease, following Gay-Lussac's Law.</p> Signup and view all the answers

<p>'1' in the equation represents the baseline pressure at 0°C, where any increase is dictated by the temperature increase (βt).</p> Signup and view all the answers

<p>To graph Gay-Lussac's Law, plot pressure (p) on the y-axis and temperature (t) on the x-axis, resulting in a straight line with a positive slope.</p> Signup and view all the answers

<p>Gay-Lussac's law states that the absolute pressure of a gas at constant volume is directly proportional to the absolute temperature of the gas.</p> Signup and view all the answers

<p>It can be represented as $\frac{p_1}{T_1} = \frac{p_2}{T_2}$, where $p_1$ and $T_1$ are the pressure and temperature of the first state, respectively.</p> Signup and view all the answers

<p>Pushing the piston down increases the pressure of the gas while decreasing its volume at constant temperature.</p> Signup and view all the answers

<p>Boyle's law states that the product of pressure and volume of a gas at constant temperature is equal to a constant, expressed as $pV = constant$.</p> Signup and view all the answers

<p>It can be concluded that the pressure and volume of a gas are inversely related; if one increases, the other must decrease.</p> Signup and view all the answers

<p>The absolute temperature in Kelvin is significant because it provides a direct proportionality in the relationship with pressure.</p> Signup and view all the answers

<p>Thermal equilibrium ensures that the temperature of the gas remains constant while measuring changes in pressure and volume.</p> Signup and view all the answers

<p>The relationship can be expressed as $p \propto \frac{1}{V}$, indicating that pressure is inversely proportional to volume.</p> Signup and view all the answers