Chem 16 Lecture 1: Matter 1

• Chemistry is the study of matter and its properties, the changes that matter undergoes, and the energy associated with those changes
• Organic Chemistry: study of compounds with carbon combined with hydrogen and sometimes few other elements such as oxygen, nitrogen, and sulfur.
• Physical Chemistry: applies the mathematical theories and methods of physics to the properties of matter and to the study of chemical processes and their accompanying energy changes
• Matter is anything that has mass and occupies space, it is the physical material of the universe
• Mass is a measure of the quantity of matter in a sample of any material
• Energy is the capacity to do work or transfer heat, it can have many different forms such as mechanical energy, light energy, heat energy, or electrical energy
• Types of Energy:

  • Kinetic energy: energy of an object in motion
  • Potential energy: energy an object possesses because of its position, condition, or composition
• All chemical processes are accompanied by energy changes, energy is conserved when converted from one form to another
• Exothermic reactions release energy to the surroundings, like combustion reactions

  Endothermic reactions absorb energy from their surroundings, like the melting of ice
• Composition refers to the types and amounts of simpler substances that make up a material
• Properties are characteristics that give each substance its unique identity and can be used to describe and distinguish it from others
• Extensive properties depend on the amount of material, like mass and volume

  Intensive properties are independent of the amount of material examined, like color, melting point, and all chemical properties
• In a chemical change, there is a change in the chemical composition of materials or substances involved, with one or more substances being used up or new substances being formed
• Pure substances cannot be further broken down or purified by physical means

  • Elements consist of only one kind of atom
  • Molecules are the smallest particle of an element or compound that can have a stable independent existence
• Compounds are substances that can be decomposed by chemical means into simpler substances, always in the same ratio by mass
• Mixtures retain the properties of their components even after mixing, can have variable composition, and can be separated by physical means
• Inorganic Chemistry: study of all other compounds, but also includes some of the simpler carbon-containing compounds such as carbon monoxide, carbon dioxide, carbonates, and bicarbonates.
• Analytical Chemistry: concerned with the detection substances present (qualitative analysis) or with the amount of each substance that is present (quantitative analysis).
• Biochemistry - study of the chemistry of processes in living organisms
• When energy is converted from one form to the other, it is

  conserved, not destroyed.
• Situations of lower energy are more stable, and therefore

  favored, over situations of higher energy (less stable)
• Chemical properties describe how a substance may react or change to form another substance.
• Physical properties can be observed without chemical alterations to the substance of interest.
• Chemical changes occurs when a substance is transformed to a chemically different substance.
• Physical change occurs when a substance changes its physical appearance but not its chemical composition.
• The two types of matter by composition are pure substances and mixtures.
• The two types of pure substances are elements and compounds.
• The two types of mixtures are homogenous mixtures and heterogenous mixtures.
• Pure substance is a matter that has fixed composition and has distinct qualities. Also only contains one kind of particle.
• Element is a substance that cannot be further separated or broken down to simpler substances by chemical means.
• Atoms are the building blocks of matter. (unique per element)
• Heterogenous mixtures are mixtures with a uniform composition all throughout.
• Homogenous mixtures are mixtures with a non-uniform composition all throughout.