Some Basic Concepts Of Chemistry Flashcards
(25 cards)
What is chemistry?
The study of matter, its properties, composition, and the changes it undergoes.
What are the three physical states of matter?
Solid, liquid, gas.
What are physical properties of matter?
Characteristics observed without changing the substance’s composition, e.g., color, odor, melting point.
What are chemical properties of matter?
Characteristics observed when a substance undergoes a chemical change, e.g., flammability, reactivity.
What system of units is commonly used in chemistry?
International System of Units (SI).
What does precision refer to in measurements?
The consistency of measurements.
What does accuracy indicate in measurements?
How close a measurement is to the true value.
What is the Law of Conservation of Mass?
Mass is neither created nor destroyed during chemical reactions.
What does the Law of Definite Proportions state?
A given compound always contains the same elements in the exact same proportion by mass.
What is the Law of Multiple Proportions?
When two elements form more than one compound, the masses of one element that combine with a fixed mass of the other are in simple whole-number ratios.
What does Dalton’s Atomic Theory propose about matter?
Matter consists of indivisible atoms.
According to Dalton’s Atomic Theory, how do atoms of the same element compare?
They are identical in mass and properties.
What is atomic mass?
The average mass of atoms of an element, considering the relative abundance of isotopes.
What is molecular mass?
The sum of the atomic masses of all atoms in a molecule.
What is a mole in chemistry?
A fundamental unit that denotes a specific number of entities (atoms, molecules, ions).
One mole equals _______.
Avogadro’s number (approximately 6.022 × 10²³ entities).
What is molar mass?
The mass of one mole of a substance, expressed in grams per mole (g/mol).
What does percentage composition refer to?
The percentage by mass of each element in a compound.
What is an empirical formula?
The simplest whole-number ratio of atoms of each element in a compound.
What is a molecular formula?
The actual number of atoms of each element in a molecule of the compound.
What does stoichiometry involve?
The quantitative relationships between reactants and products in a chemical reaction.
What is a limiting reagent?
The reactant that is entirely consumed first, limiting the amount of products formed.
What is molarity (M)?
Moles of solute per liter of solution.
What is molality (m)?
Moles of solute per kilogram of solvent.
