🔥 What is Thermochemistry?

Thermochemistry is the branch of chemistry that studies the energy changes (mainly heat) that occur during chemical reactions and physical processes. It helps us understand how much energy is absorbed or released in a reaction.

⚖️ Formula for Heat

The most common formula in thermochemistry is:

q = m × c × ΔT

– q = Heat absorbed or released (Joules)
– m = Mass of substance (grams)
– c = Specific heat capacity (J/g·°C)
– ΔT = Temperature change (°C)

📘 Example

If we heat 100 g of water (c = 4.18 J/g·°C) and its temperature rises by 25 °C:

q = 100 × 4.18 × 25 = 10,450 J

This means 10.45 kJ of heat energy was absorbed by the water.

✅ Applications

• Understanding energy flow in chemical reactions.
• Measuring heat changes in laboratory experiments.
• Used in calorimetry, fuel studies, and material science.