IndietroGeneral Chemistry: Chapter 1 Key Concepts
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Termini in questo insieme (23)
Chemistry is the study of matter and the changes it undergoes, with the atom being its basic functional unit.
Matter is anything that occupies space and has mass.
1. Element: simplest type of matter composed of one kind of atom.
2. Compound: matter composed of two or more different elements chemically bonded.
3. Mixture: matter composed of elements and/or compounds physically mixed.
A change in the physical state of a substance without changing its composition.
A change that alters chemical composition, creating new chemical bonds and products.
Reversible changes can be undone to restore original structure (e.g., phase changes).
Irreversible changes are permanent and cannot be undone (e.g., burning wood).
A property observed during a chemical reaction where matter changes into a new substance.
A measurable property describing the state of a compound, observable without changing its chemical structure.
Properties that do not depend on the amount of substance present, such as melting point and density.
Properties that depend on the amount of substance present, such as mass and volume.
Temperature is the average kinetic energy of an object and a measure of thermal energy.
Heat is the transfer of thermal energy from an object at higher temperature to one at lower temperature.
Degrees Celsius (ºC), Fahrenheit (ºF), and Kelvin (K).
A method to express very large or small numbers as a coefficient (≥1 and <10) multiplied by 10 raised to an integer exponent.
The International System of Units includes seven base units such as meter (length), kilogram (mass), second (time), mole (amount of substance), ampere (electric current), kelvin (temperature), and candela (luminous intensity).
Prefixes that modify base units by powers of ten, e.g., kilo (10³), milli (10⁻³), micro (10⁻⁶).
Digits in a measurement that contribute to its precision, including all known digits plus one estimated digit.
The result should have the same number of significant figures as the factor with the least significant figures.
The result should have the same number of decimal places as the value with the least decimal places.
A ratio that relates two different units, used to convert from one unit to another.
A method to convert units by multiplying by conversion factors to cancel unwanted units and isolate desired units.
Density is the amount of mass per unit volume, commonly expressed as g/cm³ for solids and liquids, and g/L for gases.
By water displacement, measuring the change in water level when the object is submerged.