Matter

Classification of Matter

Matter is anything that has mass and occupies space. It can be classified into pure substances and mixtures, each with distinct properties and examples.

• Pure Substance: Composed of only one type of particle. Can be an element or a compound.

• Mixture: Contains two or more substances physically combined. Can be homogeneous (uniform composition) or heterogeneous (non-uniform composition).

Elements

• Helium (He): All atoms are the same.

• Sulfur (S)

• Iron (Fe)

• Lead (Pb)

• Copper (Cu)

• Zinc (Zn)

• Tungsten (W)

Compounds

• Sugar (C12H22O11): Composed of carbon, hydrogen, and oxygen atoms chemically bonded.

Mixtures

• Homogeneous Mixtures: Uniform throughout. Example: Air.

• Heterogeneous Mixtures: Not uniform. Example: Salad.

Physical and Chemical Properties

Properties of Substances

Substances can be described by their physical and chemical properties. For example, sugar is soft and composed of simple molecules, while proteins are hard and form complex structures.

• Sugar: Soft, composed of simple molecules, provides energy.

• Protein: Hard, forms spheres, essential for body structure and function.

• White substances: Often lack antioxidants.

• Winter-grown substances: Grown under snow, tend to be more nutritious than those grown in spring or summer.

Measurement and Units

Metric System and Conversions

Chemistry relies on precise measurement. The metric system is commonly used, with units such as meters, liters, and grams.

• Length: Kilometer (km), meter (m), centimeter (cm), micrometer (μm)

• Volume: Liter (L), milliliter (mL), cubic centimeter (cm3)

• Mass: Gram (g), kilogram (kg)

Common conversions:

• 1 m = 100 cm

• 1 m = 39.37 in

• 2.54 cm = 1 in

• 1 L = 1.057 qt

• 0.946 L = 1 qt

Example conversion:

• To convert 20 cm to inches:

Density and Volume Displacement

Density

Density is a physical property defined as mass per unit volume.

• Formula:

• Units: g/cm3 or g/mL

• Example: Density of mercury is 13.6 g/mL

Volume Displacement

Volume displacement is a method to measure the volume of an irregular object by observing the change in water level.

• Initial volume: 20.2 mL

• Final volume after object added: 23.6 mL

• Volume of object:

Specific Gravity

Definition and Calculation

Specific gravity is the ratio of the density of a substance to the density of water.

• Formula:

• Density of water: 1.00 g/mL

Acids, Bases, and Salts

Definitions and Examples

Acids and bases are important classes of compounds in chemistry. Their reaction produces water and a salt.

• Acid: Substance that donates protons (H+).

• Base: Substance that accepts protons or donates hydroxide ions (OH-).

• Acid + Base → Water + Salt

Common Compounds

• Baking Soda (NaHCO3): Sodium bicarbonate, used in baking and as a refrigerator deodorizer.

• Washing Soda (Na2CO3): Sodium carbonate, used for cleaning and softening water.

• Lye (NaOH): Sodium hydroxide, a strong base used in soap making and cleaning.

Additional info:

• Some notes reference nutrition and antioxidants, which are more related to biochemistry but can be included as context for chemical composition and properties.

• Volume displacement and density calculations are foundational laboratory techniques in chemistry.

• Classification of matter into elements, compounds, and mixtures is a core concept in introductory chemistry.