Appendix A – Chemistry, Matter, and Measurements (Video Notes)

Flashcards covering key concepts from Appendix A: Chemistry, Matter, and Measurements (Video Notes)

What is chemistry?

The study of matter.

What is matter?

Anything that has mass and takes up space.

What is science?

The process by which we learn about the natural universe by observing, testing, and generating models that explain observations.

What are the general steps of the scientific method?

Propose a hypothesis, test the hypothesis, and refine/modify the hypothesis as needed.

What is a hypothesis?

A testable idea.

What is a theory?

A general statement that describes a large set of observations and data.

What is a physical property?

A characteristic of matter such as size, shape, or color.

What is a chemical property?

A characteristic that describes how matter changes its chemical structure or composition.

What is a substance?

Any sample of matter with the same physical and chemical properties throughout.

What is an element?

A substance that cannot be broken down into simpler chemically components.

What is a compound?

A substance that can be broken down into simpler chemically components.

What is an atom?

The smallest part of an element that maintains the identity of that element.

What is a molecule?

The smallest part of a compound that maintains the identity of that compound.

What is macroscopic?

A view of the universe in which one is working with large numbers of atoms or molecules at a time.

What is microscopic?

A view of the universe in which one is working with a few atoms or molecules at a time.

What is a mixture?

A sample composed of two or more substances.

What is a heterogeneous mixture?

A mixture that is a combination of two or more substances and is not uniform.

What is a homogeneous mixture (solution)?

A mixture that acts as a single substance so that it is not obvious that two or more substances are present.

What is a phase?

A certain form of matter that includes a specific set of physical properties.

What are the defining properties of a solid?

Definite shape and definite volume.

What are the defining properties of a liquid?

Definite volume but not a definite shape; takes the shape of its container.

What are the defining properties of a gas?

No definite shape or definite volume; expands to fill its container.

What is a phase change?

A physical process in which a substance goes from one phase to another.

What does melting (fusion) refer to?

Phase change from solid to liquid.

What is a mixture's two subtypes?

Heterogeneous mixture and homogeneous mixture (solution).

What is volume?

The amount of space that a given substance occupies.

What is a substance's volume measured in commonly?

Liters (L) or cubic meters (m^3); 1 L ≈ 1.06 qt and 1 cm^3 = 1 mL.

What is a derived unit?

A unit that is a combination of SI base units.

What is the SI base unit for length?

Meter (m).

Name the seven SI base units and their symbols.

Meter (m), kilogram (kg), second (s), mole (mol), kelvin (K), ampere (A), candela (cd).

What is the SI unit for energy?

Joule (kg·m^2/s^2).

What are common density units for solids and liquids?

g/cm^3 or g/mL; for gases, g/L.

What is the relationship between 1 cm^3 and 1 mL?

They are equal: 1 cm^3 = 1 mL.

What is a liter equivalent to in cubic centimeters?

1 L = 1000 cm^3.

What is the relation between Kelvin and Celsius?

K = °C + 273.

Name a common conversion factor to convert miles to kilometers.

1 mile = 1.609 km.

What is the concept of scientific notation?

A system for expressing very large or very small numbers in a compact manner; uses a power (exponent).

What is the power in scientific notation?

The exponent in a number expressed in scientific notation.

What is a significant figure?

All digits known with certainty plus the first uncertain digit.

What are the rules for significant figures: nonzero digits?

All nonzero digits are significant.

Are captive (embedded) zeros significant?

Yes; zeros between significant digits are significant.

Are leading zeros significant?

No; zeros at the beginning of a decimal number less than 1 are not significant.

Are trailing zeros significant?

Significant only if the number has a decimal point.

What is the rule for addition and subtraction with significant figures?

Align decimals and limit the answer to the rightmost column for which all numbers have significant figures.

What is the rule for multiplication and division with significant figures?

Limit the result to the least number of significant figures among the factors.

What is the role of a conversion factor?

A fraction with equivalent quantities in the numerator and denominator expressed in different units.

Are numbers from conversion factors considered in significant figures?

No; conversion factors are exact numbers and do not affect significant figures.

What is an exact number?

A number that is defined or counted, such as a dozen.

What is the relationship between temperature and Kelvin/Celsius?

Temperature in Kelvin is Celsius temperature plus 273 (K = °C + 273).

What is an example of a common SI prefix meaning 10^3?

Kilo- (k) means 10^3 (1,000).

What is an example of a common SI prefix meaning 10^-3?

Milli- (m) means 10^-3 (0.001).

What is an example of a common SI prefix meaning 10^-6?

Micro- (µ) means 10^-6 (0.000001).

What is the general description of the scientific method in one sentence?

An organized procedure for learning answers to questions through hypothesis, experimentation, and refinement.

What is the definition of a hypothesis in the scientific method?

A testable idea that can be investigated by experiments.