Question
A.substance is heated at constant rate and its temperature is taken every minute During the heating, the substance undergoes one change of state The results are shown on the graph in Figure 5. Explain the shape of the graph in terms of the changes in the movement and arrangement of the particles as the substance is heated.
Answer
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Rhian
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Answer
The graph initiates with a straight-line slope indicating the substance in its solid state where temperatures rise with constant heating. Upon reaching a certain point, despite continuous heat, temperature remains constant symbolizing the phase transition or the meltings point, demonstrating changes in particles' arrangement within the substance. Following this phase, the temperature starts increasing again indicating the alteration in flecks have occurred, and we now have a liquid. The graph then showcases another phase of a constant temperature known as boiling translating to where the liquid transfigures entirely into a gaseous state indicating subsequent changes in particles' formation.
Explanation
## Step 1:In the graph's initial stage when the material suffers minimal heat exposure, the slope gives a straight line. This rise in temperature portrays that the particles of the substance are still in their initial setup; the substance exists at this point mainly in its solid state.## Step 2:Moving forward, there's a constant level of temperature over a period. The temperature doesn't show any inclination, even though heating continues, due to what's known as the phase transition. This period portrays that the material is changing its state. There's an alteration in the overall particle arraignment of the substance (melting if it is a solid transitioning into a liquid or boiling if a liquid transitioning into a gas). During this period, the molecular motion instead of increasing the substance's temperature goes into mitigating these changes in configuration and ultimately the substance's state.## Step 3:Then again lies another linear knee-length curve showcasing increased temperature eventually reaching its peak. This indicates that the substance is now in its changed state (either as a liquid or a gas depending on what its initial state was), the implemented heat is increasing the attribute of molecular/atomic movement within the substance, thereby raising its temperature. ## Step 4:Lastly, upon reaching the peak of temperature, the substance once again exists in a suspended mode of constant temperature. This could indicate another phase transition is occurring, wherein the substance is usually changing into the gaseous state from the liquid one. This is often denominated as the boiling point. The substance vibrations due to gaining heat get transiently converted to break the true inter-molecular relationships converting the entire substance into gas from its erstwhile liquid state.