1. Temperature and Temperature Scales

1. Temperature and Temperature Scales

Concept Explanation:

Temperature is a measure of the average kinetic energy of the particles in a substance. It determines the direction of heat transfer between two objects. There are several temperature scales commonly used:

Celsius (°C): Based on the freezing point (0°C) and boiling point (100°C) of water at standard atmospheric pressure.

Fahrenheit (°F): Used mainly in the United States, with the freezing point of water at 32°F and the boiling point at 212°F.

Kelvin (K): The absolute temperature scale used in scientific measurements, starting from absolute zero, where molecular motion theoretically ceases. The freezing point of water is 273.15 K and the boiling point is 373.15 K.

Example Problem:

Convert a temperature of 25°C to Fahrenheit and Kelvin.

Solution:

To convert from Celsius to Fahrenheit:

F = (9/5)C + 32

F = (9/5)(25) + 32 = 77°F

To convert from Celsius to Kelvin:

K = C + 273.15

K = 25 + 273.15 = 298.15 K

So, 25°C is equivalent to 77°F and 298.15 K.