Presentation on theme: "Ch. 1 – Matter and Its Properties. Scientific Method Steps Ask a __________________________ Observe and collect data Formulate a hypothesis (a."— Presentation transcript:
Scientific Method Steps Ask a __________________________ Observe and collect data Formulate a hypothesis (a testable if-then statement). The hypothesis serves as a basis for making predictions and for carrying out further experiments. Test your ______________________ – Requires experimentation that provides data to support or refute your hypothesis.
Terms to Know Law vs. theory Scientific (natural) _____________: a general statement based on the observed behavior of matter to which no exceptions are known. __________________: a broad generalization that explains a body of facts or phenomena. Quantitative vs. qualitative data Quantitative: numerical (__________________________________) Qualitative: descriptive (___________________________________)
Properties & Changes in Matter Extensive vs. Intensive Physical vs. Chemical
A. Extensive vs. Intensive Extensive Property depends on the amount of matter present Intensive Property depends on the identity of substance, not the amount
A. Extensive vs. Intensive Examples: boiling point volume mass density conductivity intensive extensive intensive
B. Physical vs. Chemical Physical Property can be observed without changing the identity of the substance Chemical Property describes the ability of a substance to undergo changes in identity
B. Physical vs. Chemical Examples: melting point flammable density magnetic tarnishes in air physical chemical physical chemical
B. Physical vs. Chemical Physical Change changes the form of a substance without changing its identity properties remain the same
B. Physical vs. Chemical Chemical Change changes the identity of a substance products have different properties
B. Physical vs. Chemical Signs of a Chemical Change change in color or odor formation of a gas formation of a precipitate (solid) change in light or heat
B. Physical vs. Chemical Examples: rusting iron dissolving in water burning a log melting ice grinding spices chemical physical chemical physical
Ch. 1 - Matter Classification of Matter (p.15-17, 397-398) Matter Flowchart Pure Substances Mixtures
A. Matter Flowchart MATTER Can it be physically separated? Homogeneous Mixture (solution) Heterogeneous MixtureCompoundElement MIXTUREPURE SUBSTANCE yes no Can it be chemically decomposed? noyes Is the composition uniform? noyes ColloidsSuspensions
A. Matter Flowchart Examples: graphite pepper sugar (sucrose) paint soda element hetero. mixture compound hetero. mixture solution
B. Pure Substances Element composed of identical atoms EX: copper wire, aluminum foil
B. Pure Substances Compound composed of 2 or more elements in a fixed ratio properties differ from those of individual elements EX: table salt (NaCl)
B. Pure Substances Law of Definite Composition A given compound always contains the same, fixed ratio of elements. Law of Multiple Proportions Elements can combine in different ratios to form different compounds.
B. Pure Substances For example… Two different compounds, each has a definite composition.
C. Mixtures Variable combination of 2 or more pure substances. HeterogeneousHomogeneous
C. Mixtures Solution homogeneous very small particles no Tyndall effect Tyndall Effect particles don’t settle EX: rubbing alcohol