Physics an

Apuntes

Physics and Chemistry study matter, its properties, composition, and the changes it goes through. • Physics focuses on the laws that describe how matter and energy behave. • Chemistry studies the composition of matter and how substances combine and transform into new ones. To study matter, we need to measure it — that’s what measurement is about. ⸻ ⚛️ Matter and Measurement Everything that has mass and occupies space is called matter. Scientists describe matter using physical quantities — characteristics that can be measured, like: • Length (longitud) • Mass (masa) • Time (tiempo) • Temperature (temperatura) • Volume (volumen) • Amount of matter (cantidad de materia) • Amount of substance (cantidad de sustancia) ⸻ 📏 Physical Quantity A physical quantity is anything that can be measured and written as a number with a unit. For example: • 5 meters → quantity: length, number: 5, unit: meter • 10 kilograms → quantity: mass, number: 10, unit: kilogram • 2 moles → quantity: amount of substance, number: 2, unit: mole 👉 Without a unit, the number doesn’t mean anything. Saying “5” is meaningless unless we say “5 meters” or “5 kilograms”. ⸻ 🌟 Amount of Matter vs. Amo...