📖 Theory & Concepts ▼

1. Phase Transitions

Property Melting Point Boiling Point
Definition Solid → Liquid Liquid → Gas
Water (at 1 atm) 0°C 100°C
Temp. during change Remains constant
Energy absorbed Latent heat of fusion Latent heat of vaporization

2. Key Concepts

  • Latent Heat Heat absorbed without temperature change. Used to overcome intermolecular forces during phase change.
  • Pressure Effect At higher altitudes (lower pressure), water boils below 100°C. At higher pressure, it boils above 100°C.
  • Purity Test Pure substances have sharp melting/boiling points. Impurities cause these to change.
Did you know? On Mount Everest, water boils at just 71°C due to the low atmospheric pressure — not hot enough to make good tea!

🎯 Lab Mode

Experimental Theory

Melting point is the temperature where solid turns to liquid. For pure ice, this is 0°C. Temperature remains constant during the phase change.

Crucial Note

Position the thermometer bulb deep in the substance without touching the beaker walls for an accurate reading.

Procedure
Pressure: 1.0 atm
Temperature
25.0 °C
Drag the thermometer into the beaker
Lab Journal
Waiting for readings...

Recorded Results

Melting Pt (Ice) ---
Boiling Pt (Water) ---