Physics and Chemistry Fundamentals

Physics and Chemistry

The scientific method is the process used to investigate natural phenomena. It involves observation, research, hypothesis formulation, experimentation, result interpretation, law formulation, theory and model development, and finally, a scientific report.

Magnitude: A measurable quantity. A crucial magnitude is defined independently; a derived magnitude is defined from other key magnitudes.

Measurement: Comparing a quantity with a unit. The result is often expressed numerically.

Unit: A standard quantity used for comparison. Units must be constant, universal, and reproducible. The International System of Units (SI) is an agreed-upon system.

Accuracy: The smallest variation a tool can measure.

Substance: Anything that has mass and volume (these are general properties of matter and don't identify specific substances).

Density: The mass per unit volume. It's a characteristic property of matter.

Kinetic Theory: Matter consists of tiny, constantly moving particles. Matter exists in three main states:

• Solid: Particles are close together and vibrate. Solids have a fixed shape and volume.
• Liquid: Particles have weaker bonds. Liquids have a fixed volume but not a fixed shape.
• Gas: Particles tend to separate and generate pressure.
• Plasma: Found in stars at high temperatures. It's a mixture of ions and electrons.
• Bose-Einstein Condensate: Particles are in a state of minimal motion.

Temperature: Measures the average kinetic energy of particles. Scales include:

• Celsius: 0°C (melting ice), 100°C (boiling water)
• Kelvin: 273 K (melting ice), 373 K (boiling water), 0 K (absolute zero)

Degrees Kelvin = Degrees Celsius + 273

Change of State: A physical process where a substance changes state without altering its chemical nature. Temperature remains constant during a change of state. Examples include melting, vaporization (evaporation, boiling, sublimation), condensation, and solidification.

Pressure: Force per unit area. Higher force means higher pressure. Measured in Pascals, millimeters of mercury, atmospheres, etc.

Melting Point: The temperature at which a solid melts at one atmosphere of pressure.

Boiling Point: The temperature at which a liquid boils at one atmosphere of pressure.

Barometer: Measures atmospheric pressure.

High Pressure: Anticyclone

Low Pressure: Storm

Boyle's Law (Mariotte's Law): For a fixed mass of gas at constant temperature, higher pressure results in lower volume, and vice versa.

Charles's Law (Gay-Lussac's Law 1st): For a fixed mass of gas at constant pressure, higher temperature results in higher volume, and vice versa.

Charles's Law (Gay-Lussac's Law 2nd): For a fixed mass of gas at constant volume, higher pressure results in higher temperature, and vice versa.