- Gallium (Ga) changes from a solid to a liquid because its melting point is \(30^{\circ}\text{C}\), which lies between \(25^{\circ}\text{C}\) and \(33^{\circ}\text{C}\).
- Nitrogen (\(N_2\)) turns into a liquid because cooling from \(-170^{\circ}\text{C}\) to \(-200^{\circ}\text{C}\) takes it from above its boiling point (\(-192^{\circ}\text{C}\)) to between its melting point (\(-210^{\circ}\text{C}\)) and boiling point.
- Gold (Au) changes from a liquid to a \(\boxed{\text{gas}}\) when heated to its boiling point of \(2{,}856^{\circ}\text{C}\).
- Final answers: \(\boxed{\text{Gallium}}\), \(\boxed{\text{turns into a liquid}}\), \(\boxed{\text{gas}}\).
Explanation
- Analyzing Phase Transitions Based on Temperature Data
To understand the behavior of these substances, we must compare the given temperatures with their respective melting and boiling points. A substance is solid if the temperature is below its melting point, liquid if the temperature is between its melting and boiling points, and gas if the temperature is above its boiling point.
- Gallium Transition: For the first question, we look for a substance that is solid at \(25^{\circ}\text{C}\) and liquid at \(33^{\circ}\text{C}\).
- Gallium has a melting point of \(30^{\circ}\text{C}\) and a boiling point of \(2{,}204^{\circ}\text{C}\).
- At \(25^{\circ}\text{C}\), \(25 < 30\), so it is solid.
- At \(33^{\circ}\text{C}\), \(30 < 33 < 2{,}204\), so it is liquid.
- Therefore, Gallium changes from a solid to a liquid in this range.
- Nitrogen Transition: For the second question, we examine the state of nitrogen when cooled from \(-170^{\circ}\text{C}\) to \(-200^{\circ}\text{C}\). Nitrogen has a melting point of \(-210^{\circ}\text{C}\) and a boiling point of \(-192^{\circ}\text{C}\).
- At \(-170^{\circ}\text{C}\), since \(-170 > -192\), nitrogen is a gas.
- At \(-200^{\circ}\text{C}\), since \(-210 < -200 < -192\), nitrogen is a liquid.
- Thus, the nitrogen turns into a liquid (condenses).
- Gold Transition: For the third question, we identify the state change of gold at \(2{,}856^{\circ}\text{C}\). Gold has a melting point of \(1{,}064^{\circ}\text{C}\) and a boiling point of \(2{,}856^{\circ}\text{C}\).
- At its boiling point, a substance transitions from a liquid to a gas. Thus, when heated to \(2{,}856^{\circ}\text{C}\), liquid gold changes into a gas.
Examples
Understanding phase changes is essential in materials science and engineering. For example, engineers designing cooling systems for electronics use these temperature thresholds to ensure components stay within safe operating ranges. By knowing the specific melting and boiling points of materials like gallium or nitrogen, they can prevent hardware from overheating or failing due to state changes in thermal interface materials or coolants.