Heating and Cooling Curves

Introduction There are four common states or phases of matter (solid, liquid, gas and plasma). We will focus on three of the four states of matter. Use your prior knowledge to label each of the 6 phase changes in the diagram below using the list of words here:Vaporization Sublimation MeltingFreezingDepositionCondensation How to Read a Heating Curve What happens to the temperature of a block of ice when you put a flame underneath it? You might think that the temperature goes up smoothly, but that's not what happens. The graph of temperature against time is called a heating curve. Let's look at the heating curve for water.Notice that, in general, the temperature goes up the longer the heating continues. However, there are two horizontal flat parts (segments BC and DE) to the graph. These happen when there is a change of state- the temperature is constant during a change in state. The flat areas are also called phase changes. The sloped areas are places where the substance is in each state of matter- AB is solid, CD is liquid, and EF is gas. The first change of state (segment BC) is melting (changing from a solid to a liquid). The temperature stays the same while a substance melts. For water, this temperature is 0°C because the melting point for water is 0°C. Over the course of this line segment, both liquid and solid exist in various ratios, starting at 100% solid and ending at 100% liquid.The second change of state (segment DE) is boiling (changing from a liquid to a gas). The temperature stays the same while a substance boils. For water, this temperature is 100°C because the boiling point for water is 100°C. Over the course of this line segment, both liquid and gas exist in various ratios, starting at 100% liquid and ending at 100% gas.Different substances have different melting points and boiling points, but the shapes of their heating curves are very similar. For example, this is the heating curve for iron, a metal that melts at 1538°C and boils at 2861°C. The following graph shows what happens to water as it goes from ice to liquid water to water vapor. Use the word bank and heating curve graph below to identify these phases and phase changes.Temperature Time Melting PointSolid Liquid Gas Boiling Point Here are the heating curves for 4 different substances. Use these curves to answer the questions that follow. Type your answers into the blank after each question.Which substance does have the highest boiling point? _What is that boiling point of this substance? _ At what temperature range is NaCl a solid? _What is the melting point for Cl2? _Which substance is a liquid at room temperature? (room temperature in Celsius is around 20-25 degrees)_What phase is Cl2 in at room temperature? _What is NaCl’s boiling point? _What phase is water in at -100˚C? _What temperature is Cl2 at after being heated for 20 minutes? _