Heating Curve for Water and Phase Change Process from Ice to Steam

I can see this is a heating curve worksheet for water. Let me analyze what's shown and work through the key concepts.

Looking at the diagram:
- It shows temperature vs. time as 10g of ice at -20°C is heated to steam at 140°C
- The heating curve has labeled segments: A-B, B-C, C-D, D-E, E-F
- Each segment represents different phases or phase changes

Let me identify what happens in each section:

Section A-B: Solid ice warming from -20°C to 0°C
- Temperature increases while staying solid
- No phase change here

Section B-C: Melting (solid → liquid) at 0°C
- Temperature stays constant at 0°C
- This is where ice melts into liquid water
- Energy goes into breaking bonds, not raising temperature

Section C-D: Liquid water warming from 0°C to 100°C
- Temperature increases while staying liquid
- No phase change here

Section D-E: Boiling/vaporization (liquid → gas) at 100°C
- Temperature stays constant at 100°C
- This is where liquid water turns into steam
- Energy goes into breaking bonds, not raising temperature

Section E-F: Steam/gas warming from 100°C to 140°C
- Temperature increases while staying gaseous
- No phase change here

The key points are:
- Plateaus (flat sections) = phase changes happening (B-C and D-E)
- Sloped sections = temperature changing within one phase (A-B, C-D, E-F)
- During phase changes, temperature doesn't change even though heat is being added

Final Answer:
The heating curve shows five distinct regions:
- A-B: Ice warming (-20°C to 0°C) - solid phase
- B-C: Melting at 0°C - phase change from solid to liquid
- C-D: Water warming (0°C to 100°C) - liquid phase
- D-E: Boiling at 100°C - phase change from liquid to gas
- E-F: Steam warming (100°C to 140°C) - gas phase

During the flat plateaus (B-C and D-E), the substance undergoes phase changes while temperature remains constant.