Physical science Review for Friday’s test Fundamental Chemistry

To do: Finish labs Review for test Go over homework

Matter Anything that has mass and occupies space

Mass The amount of material that makes up an object Units: kg

Volume The amount of space occupied by an object Units cm 3 or ml Relationship between units is 1 to 1

Element A substance that can not be broken down or separated into simpler substances by chemical means Basic components Listed on the periodic table (know the element’s name identified in class)

atom The smallest unit of an element that maintains the properties of the element

Compound A substance made of two or more different elements that are combined chemically Properties of compounds may not be the same as properties of elements Be able to name at least 3 common compounds talked about in class

What are the 3 most abundant elements that make up the earth? Oxygen Iron silicon

What are 3 most common elements that make up a human being? Oxygen Carbon hydrogen

Molecule The smallest unit of a substance that keeps all of the physical and chemical properties of that substance

What do chemical formulas show? A combination of element symbols and numbers that represent the chemical make up of a substance

What do the subscripts mean in a chemical formula? The number of atoms needed of a particular element to make one molecule of that substance

What does it mean if there is no subscript? Only need one atom of that substance to make a molecule

Pure substance Substance composed of either one element or one compound Fixed composition

Mixture A combination of 2 or more pure substance combined physically Classified by how thoroughly they are mixed Properties of mixture similar to properties of components

Heterogeneous mixture Mixtures that do not mix well Examples:

Homogeneous Mixture Mixtures that mix very well Solutions, substances dissolve well Examples:

Miscible mixture Like homogeneous Dissolve completely

Immiscible mixture Like heterogeneous Don’t mix well at all Examples

Polyatomic forms of elements Atoms that can not be found alone Are naturally found connected to others

Physical properties of matter Any property that provides a physical description of an object Described by senses Easy to observe Help to determine uses for matter

Examples of physical properties Includes state of matter Melting/freezing point Density

Melting/Boiling/Freezing points The temperature when an object changes it’s state of matter

Density The ratio of the mass to the volume of an object How heavy the object feels

What is the density of water? 1 g/cm 3

Solve for density, mass or volume Equation

Chemical properties of matter Chemical properties describe how a substances react with other substances

Reactivity The ability of a substance to combine chemically with another substance To form a new substance To break into new substances Examples:

Flammability The ability of a substance to react in the presence of oxygen and burn when exposed to a flame Examples of material that is not flammable

Examples of characteristic properties A change Those properties most useful in identifying and classifying substances examples

Physical changes A change that affect one or more physical properties without changing the substances identity Examples: melting, dissolving

Chemical changes Changes to an object that allow it to form new substances New substances with different properties Can detect chemical change Can not be reversed by physical means

Homework pg 62 Problems ) 150,000 g 28) 210 g 29) glycerin is less dense (1.26 g/ml) 30) filters, dissolve salt, evaporation 31) compound, chemical changes took place

homework 32) crushed shape, metallic, shiny 33) a physical change 34) density stays the same of the metal not the can 35) no, can tell chem properties only through chemical change 36) high melting point, hardness and strength

Homework quiz Describe a procedure to separate a mixture of salt, nails and oil