__ Choose which of the following is NOT true: Liquefaction of the gas occurs at approximately -155^circ C Condensation occurs at 0^circ C Absolute zero on the Kelvin scale is equivalent to -273^circ C The gas follows a linear relationship between volume and temperature.

To determine which statement is NOT true, let's analyze each one:<br /><br />1. **Liquefaction of the gas occurs at approximately $-155^{\circ }C$:**<br /> - Liquefaction refers to the process of a gas turning into a liquid. The temperature at which this occurs depends on the specific gas in question. Without additional context about which gas is being referred to, it's difficult to assess the truth of this statement universally.<br /><br />2. **Condensation occurs at $0^{\circ }C$:**<br /> - Condensation is the process where a gas turns into a liquid. For water vapor, condensation typically occurs at $0^{\circ }C$ (the freezing/melting point of water). However, for other gases, condensation can occur at different temperatures. This statement is true specifically for water.<br /><br />3. **Absolute zero on the Kelvin scale is equivalent to $-273^{\circ }C$:**<br /> - Absolute zero is the lowest possible temperature where all molecular motion stops. On the Celsius scale, absolute zero is approximately $-273.15^{\circ }C$. Therefore, this statement is essentially true, though it should be noted that the exact value is $-273.15^{\circ }C$.<br /><br />4. **The gas follows a linear relationship between volume and temperature:**<br /> - According to Charles's Law, for an ideal gas at constant pressure, the volume of the gas is directly proportional to its temperature (in Kelvin). This implies a linear relationship between volume and temperature. This statement is generally true for ideal gases.<br /><br />Given these analyses, the statement that is NOT universally true without additional context is the first one: "Liquefaction of the gas occurs at approximately $-155^{\circ }C$," as it depends on the specific gas being considered.