exam 1 chem

Chemistry Overview

• The Central Science: Chemistry is crucial for understanding various scientific disciplines.

Scientific Method

• Follows a systematic process involving open inquiry and reworking of questions based on findings.

Domains of Chemistry

• Macroscopic: Water in various forms (ice, liquid, vapor).

• Microscopic: Behavior of molecules in different states.

• Symbolic: Chemical formulas (e.g., H2O for water).

Phases and Classification of Matter

• States of Matter:

  • Solid: Fixed shape and volume.

  • Liquid: Takes the shape of the container but has a fixed volume.

  • Gas: Expands to fill its container.

• Mixtures: Distinguished as homogeneous (uniform composition) or heterogeneous (non-uniform composition).

• Law of Conservation of Matter: Mass is conserved in chemical reactions.

Chemical Properties and Changes

• Chemical Properties:

  • Example: Iron rusts, while chromium does not.

• Chemical Changes:

  • Examples:

    • Copper reacts with nitric acid.

    • Combustion of a match.

    • Cooking red meat.

Elements and Compounds

• Elements combine to form molecules; compounds consist of different elements in fixed ratios.

• Periodic Table Basics:

  • Elements categorized by atomic number and properties.

Measurements in Chemistry

• Basic Units: Length (meter), mass (kilogram), volume (liter), density (g/cm³), temperature (Kelvin).

• Significant Figures: Rules for determining how many digits to report based on measurement precision.

Scientific Notation

• Used for expressing large or small numbers conveniently, indicating the number of significant figures clearly.

Temperature Conversions

• Conversions between Fahrenheit, Celsius, and Kelvin, emphasizing direct relationships.

Conclusion

• Understanding these fundamental concepts in chemistry is essential for further studies and applications.