PDFDocument_CHAPTER_1

What are atoms?

Submicroscopic particles that constitute the fundamental building blocks of ordinary matter.

How do atoms and molecules affect the behavior of matter?

Atoms and molecules determine how matter behaves; different properties lead to different behaviors.

What is the difference between a compound and an element?

A compound consists of two or more different types of atoms, while an element contains only one type of atom.

What defines the states of matter?

States of matter (solid, liquid, gas) are defined by molecular arrangement and how particles interact.

What is a hypothesis?

A tentative interpretation or explanation of observations that must be testable and simple.

What is a scientific law?

A brief statement that summarizes past observations and predicts future ones; it is a universal principle.

What distinguishes a scientific theory from a scientific law?

A theory explains why nature does what it does, while a law summarizes what nature does.

Define homogeneous mixture.

A mixture that has a uniform composition throughout.

Define heterogeneous mixture.

A mixture whose composition varies from one region to another.

What is the difference between a physical change and a chemical change?

A physical change alters appearance without changing composition; a chemical change alters the composition of the substance.

What is Sublimation?

Sublimation is the process where a solid changes directly into a gas without passing through the liquid phase, often occurring under specific temperature and pressure conditions.

What is deposition?

Deposition is the process where a gas changes directly into a solid without passing through the liquid phase, typically occurring under specific temperature and pressure conditions.

What is energy in terms of physical and chemical changes?

Energy is the capacity to do work, and it is always conserved during physical or chemical changes.

What is Sate Function?

A state function is a property of a system that depends only on its current state, not on the path taken to reach that state. Examples include temperature, pressure, and volume.

What are significant figures?

Digits that carry meaning contributing to a measurement's precision.

What is the metric system used for in chemistry?

It's the common standard for specifying measurements in chemistry.

What is the absolute zero in the Kelvin scale?

0 Kelvin, the lowest temperature possible where molecular motion virtually stops.

What is dimensional analysis?

A method used to convert units by treating measurement units as algebraic quantities.

What are the two types of pure substances?

Elements and compounds.

What happens during a sublimation?

A solid transitions directly to a gas state.

Explain the concept of precision in measurements.

Precision refers to how closely repeated measurements agree with each other.

What is the purpose of using scientific notation?

To express very large or very small numbers succinctly and clearly.

What does it mean if a mixture is described as being separable?

The components of the mixture can be separated based on their physical or chemical properties.

What role does density play in classifying substances?

Density affects whether a substance will sink or float in another substance.

Define intensive property.

An intensive property is independent of the amount of substance, like density.

What factors determine the quantity of significant figures in a number?

Rules include nonzero digits are significant, leading zeros are not, and trailing zeros depend on decimal placement.

How does a conversion factor work in dimensional analysis?

A conversion factor is a ratio that expresses how many of one unit are equivalent to another, aiding in unit conversion.