Question

An ideal gas is one which obeys the gas laws under (1) a few selected experimental conditions (2) all experimental conditions (3) low pressure alone (4) high temperature alone

Short answer

An ideal gas obeys the gas laws under all experimental conditions (Option 2).

Step-by-step solution

Understand the Definition of an Ideal Gas

An ideal gas is a theoretical concept where gas particles do not interact and occupy no volume. This model is useful in explaining the behavior of gases under various conditions.

Review the Gas Laws

Gas laws like Boyle's Law, Charles's Law, and Avogadro's Law describe the behavior of an ideal gas. These laws apply when internal forces between gas molecules are negligible.

Identify Conditions for Ideal Gas Behavior

Ideal gas behavior is most accurately observed at high temperature and low pressure. Under these conditions, interactions between gas molecules are minimal, making the ideal gas approximation valid.

Analyze the Given Options

Given the options:(1) a few selected experimental conditions(2) all experimental conditions(3) low pressure alone(4) high temperature aloneRealize that (2) is unrealistic because gases will deviate from ideal behavior at high pressures and low temperatures.

Select the Best Answer

Considering the previous analysis, the best answer is that an ideal gas obeys the gas laws under all experimental conditions where it behaves ideally, which mainly includes high temperature and low pressure.

Key concepts

Ideal Gas Laws

Ideal gas laws form the foundation for our understanding of gas behavior. These laws outline how gases respond to changes in pressure, volume, and temperature. The three main laws are Boyle's Law, Charles's Law, and Avogadro's Law. Boyle's Law describes the inverse relationship between the pressure and volume of a gas at constant temperature.
Charles's Law explains how the volume of a gas changes directly with temperature at constant pressure. Avogadro's Law states that the volume of gas is directly proportional to the number of moles, given constant temperature and pressure. These laws are best utilized under conditions where interactions between gas molecules are negligible, which is not always the case in real-life situations.

Gas Behavior

Understanding gas behavior is crucial in the study of thermodynamics and physical chemistry. Gases consist of particles that are constantly in motion, colliding with each other and the walls of their container. The behavior of gases can be predicted by observing changes in pressure, volume, and temperature. Most gases deviate from ideal behavior due to intermolecular forces and the volume occupied by gas particles.
This deviation is less significant under conditions where gases behave ideally, notably at high temperatures and low pressures. By studying gas behavior under these ideal conditions, we can approximate how gases will react to different changes in their environment.

High Temperature and Low Pressure

The conditions of high temperature and low pressure are crucial for gases to behave ideally. At high temperatures, gas particles have more kinetic energy, reducing the effect of intermolecular attractions. This means gas particles move freely and independently. At low pressures, gas molecules are spread out, minimizing interactions between them.
This combination of conditions allows gases to follow the ideal gas laws more closely. An ideal gas is an excellent theoretical model because it simplifies the complex interactions that occur in real gases. By creating environments with high temperatures and low pressures, we can better study and predict gas behavior based on the ideal gas assumptions.

Boyle's Law

Boyle's Law is one of the primary gas laws and states that the pressure of a given mass of gas is inversely proportional to its volume, provided the temperature remains constant. Mathematically, this is expressed as: \[ P_1V_1 = P_2V_2 \] where \(P\) represents pressure and \(V\) represents volume.
When you decrease the volume of a gas, the pressure increases, assuming the temperature doesn't change. This relationship is crucial in understanding how gases will behave when compressed or expanded. Boyle's Law is applicable under conditions where other gas laws are held constant, and it helps us predict changes in gas environments.

Charles's Law

Charles's Law describes the direct relationship between the volume and temperature of a gas at constant pressure. Formulated as: \[ \frac{V_1}{T_1} = \frac{V_2}{T_2} \] where \(V\) is volume and \(T\) is temperature, measured in Kelvins.
According to Charles's Law, if you increase the temperature of a gas, its volume will also increase, assuming the pressure remains the same. This is due to the increase in kinetic energy of gas particles, causing them to move more and occupy more space. Understanding this law is vital for predicting how gases will react when heated or cooled. Like other ideal gas laws, it works best under ideal conditions.