Test Review Unit 1: Classification of Matter and Measurement (Chapters 1-3) - Zumdahl Introductory Chemistry: A Foundation (8th ed.)

Fifty practice flashcards covering core concepts from Classification of Matter and Measurement.

What is matter?

Anything that has mass and occupies space.

Name the three states of matter and a key property of each.

Solid—definite shape and volume; Liquid—definite volume, takes shape of container; Gas—no definite shape or volume, expands to fill space.

How do elements differ from compounds? Give examples.

Elements are pure substances made of one kind of atom (e.g., H, O); compounds are two or more elements chemically bonded (e.g., H2O, NaCl).

What change converts elements to compounds or compounds to elements?

A chemical change (chemical reaction) is required.

Define a mixture.

A combination of two or more substances not chemically bonded; components retain identities.

How do homogeneous and heterogeneous mixtures differ? Give examples.

Homogeneous mixtures have uniform composition (e.g., saline solution, air); heterogeneous mixtures have visibly different parts (e.g., salad, granite).

Provide examples of homogeneous mixtures.

Saltwater, air, sugar in water (sucrose solution).

Provide examples of heterogeneous mixtures.

Trail mix, granite, salad with mixed components.

List four separation methods for mixtures.

Evaporation, distillation, filtration, chromatography.

What is evaporation used for in mixture separation?

Removal of a solvent by vaporization, leaving dissolved solute.

What is distillation used for?

Separation based on differences in boiling points; purification.

What is filtration used for?

Separation of a solid from a liquid using a filter.

What is chromatography used for?

Separation based on differential affinity to stationary/mobile phase; separates components.

Give examples of physical changes.

Melting ice, boiling water, dissolving sugar (no chemical reaction).

Give examples of chemical changes.

Rusting iron, combustion of fuel, baking a cake.

Differentiate qualitative and quantitative measurements.

Qualitative—descriptive (color, shape); quantitative—numeric values (mass, length).

What are the two components of every measurement?

A numerical value and a unit.

Define accuracy.

How close a measurement is to the true value.

Define precision.

How reproducible or consistent measurements are.

Define systematic error.

A consistent bias that shifts all measurements in one direction.

How can systematic error be minimized?

Calibrate instruments, use standards, improve procedures.

Define random error.

Unpredictable fluctuations causing scatter around the true value.

How can random error be minimized?

Take multiple measurements and average.

What are significant figures?

Digits that carry meaning about precision in a measurement.

What is the rule for significant figures in multiplication/division?

The result has as many significant figures as the factor with the fewest SFs.

What is the rule for significant figures in addition/subtraction?

The result should be rounded to the least precise decimal place (fewest decimal places).

How do you convert a number into scientific notation?

Move the decimal so the coefficient is between 1 and 10; multiply by 10^n, where n reflects the decimal shift.

List metric prefixes from pico to mega and their abbreviations.

Pico (p, 10^-12); Nano (n, 10^-9); Micro (μ, 10^-6); Milli (m, 10^-3); Centi (c, 10^-2); Deci (d, 10^-1); Kilo (k, 10^3); Mega (M, 10^6).

What are the base SI units for mass, length, and time?

Mass — kilogram (kg); Length — meter (m); Time — second (s).

What is dimensional analysis?

A problem-solving method using conversion factors to cancel units and ensure dimensional consistency.

What are the steps in performing dimensional analysis?

Identify starting unit and target unit; write equivalence statements; set up conversion factors; chain them; cancel unwanted units; ensure wanted units remain; compute.

What is a T-chart in dimensional analysis?

A two-column setup used to organize units and conversions to track cancellations.

What is the purpose of writing equivalence statements in dimensional analysis?

To relate units through conversion factors so that units cancel appropriately.

How do you set up conversion factors in dimensional analysis?

Place the unit you want to cancel on opposite sides so the units cancel as you multiply.

What does it mean to cancel unwanted units in dimensional analysis?

Cross out units that appear both in numerator and denominator as you progress toward the desired unit.

What is the rule about the placement of numbers on top vs bottom in dimensional analysis?

Place numbers with factors you multiply in the numerator; denominators in the opposite side; maintain proper fractions.

What temperature scales are commonly used in chemistry?

Celsius, Fahrenheit, Kelvin.

How do you convert Celsius to Kelvin?

K = C + 273.15.

How do you convert Celsius to Fahrenheit?

F = (9/5)C + 32.

How do you convert Fahrenheit to Celsius?

C = (F − 32) × 5/9.

How do you convert Fahrenheit to Kelvin?

K = (F − 32) × 5/9 + 273.15.

How do you convert Kelvin to Celsius?

C = K − 273.15.

How do you calculate density?

Density = mass / volume.

What are common density units?

g/mL for liquids, g/cm^3 for solids; kg/m^3 in SI.

How can you determine volume using water displacement?

Record initial water volume, submerge object, record final volume, volume = final − initial.

What is a pure substance?

A substance with fixed composition; either an element or a compound.

What is an element? Provide examples.

Substance consisting of only one type of atom; e.g., H, O, Fe.

What is a compound? Provide examples.

Substance composed of two or more elements chemically bonded; e.g., H2O, NaCl.

What is the difference between a pure substance and a mixture?

Pure substances have fixed composition (elements or compounds); mixtures contain two or more substances not chemically bonded.

What are examples of physical changes vs chemical changes?

Physical changes: melting, freezing, dissolving (no chemical change); Chemical changes: burning, rusting, cooking (chemical bonds break/form).