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This book provides a comprehensive understanding of matter and the changes it undergoes, covering topics such as the states of matter, solutions, pure substances, compounds, and physical and chemical changes. It explores the fundamentals of chemistry and their applications in general, organic, and biochemistry.
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Fundamentals of General, Organic, and BiochemistryFifth EditionbyMcMurry, Castellion, and Ballantine
Chemistry: • The study of matter and the changes it undergoes. • Define matter • What is meant here by change?
Three States of Matter • Solid: rigid - fixed volume and shape • Liquid: definite volume but assumes the shape of its container • Gas: no fixed volume or shape - assumes the shape of its container • Link to Video
Check Appearance • Ahomogeneous mixturecalled a solution looks like pure substances which are also homogeneous • Aheterogeneous mixtureis, to the naked eye, clearly not uniform
Pure Substances • Can be isolated from mixtures by separation methods: • Chromatography • Filtration • Distillation • Recrystalization
Pure Substances • Pure substances have specific unchanging physical and chemical properties. • Percent by mass of each element • Melting points, Boiling points • Density at specified temperature • Many other properties
Compound:A substance with a constant composition that can be broken down into elements by chemical processes. Element:A substance that cannot be decomposed into simpler substances by chemical means.
Changes in Matter • Physical Changes are changes to matter that do not result in a change in the fundamental components that make that substance • State Changes – boiling, melting, condensing • If you are talking about a specific substance we call it a Physical Property of that substance.
Changes in Matter • Chemical Changes involve a change in the fundamental components of the substance • Produce a new substance • Specific substance = Chemical Property
Classify Each of the following as Physical or Chemical Changes • Iron is melted. • Physical change – describes a state change, but the material is still iron. • Iron combines with oxygen to form rust.. • Chemical Property of Iron – describes how iron and oxygen react to make a new substance, rust • Sugar ferments to form ethyl alcohol. • Chemical change – describes how sugar becomes a new substance
Chemistry: • What do you know? • What do you think? • What do you believe?
HypothesisExplains an observation. May be changed as soon as new information comes available. Must be testable.
ExperimentationChecking your hypothesis by testing the “what if”
Steps in the Scientific Method 1. Observations quantitative qualitative 2. Formulating hypotheses possible explanation for the observation 3. Performing experiments gathering new information to decide whether the hypothesis is valid
Outcomes Over the Long-Term Theory (Model) A set of tested hypotheses that give an overall explanation of some natural phenomenon. Natural Law The same observation applies to many different systems Example - Law of Conservation of Mass
Law vs. Theory A law summarizes what happens. A theory is an attempt to explain why something happens.
The various parts of the scientific method. Note that The Law comes from the observations of the many experiments and does not attempt to explain the observations. The theory explains the observations.
