Genchem LESSON 1

• PLASMA

  It is a hot ionized gas consisting of approximately equal numbers of positively charged ions and negatively charged electrons.

  
  

  The characteristics of plasmas are significantly different from those of ordinary neutral gases SO that plasmas are considered a distinct "fourth state of matter."
• According to change involved During the measurement of the property

  Physical properties Chemical properties
• According to dependence on the amount of matter

  Intensive Properties

  Extensive Properties
• Physical properties - Anything that can be measured without changing the identity or chemical composition of the substance.nvolves the formation of a new arrangement of matter but the structure of the atoms and molecules remains the same.

  volves the formation of a new arrangement of matter but the structure of the atoms and molecules remains the same.

  -Involves the formation of a new arrangement of matter but the structure of the atoms and molecules remains the same.
• Chemical Properties Refers to the property of a substance that can be observed or measured when the substance undergoes a chemical change by performing a chemical reaction. -When a chemical change happens the molecular structure of a substance changes.
• Combustibilty

  Whether the substance undergoes combustion or not
• Stability

  Whether the substance can be easily decomposed or not
• Reactivity

  Whether it reacts with acids, bases, and oxygen, gas or not
• Relative Actinty

  Whether the material is more active or less active than other members of its chemical family
• lonization

  Whether it will break into charged particles when in solution with water or not
• Toxicity

  Whether substance can damage an organism or not
• Intensive Properties - is one that does not depend on the mass of the substance or system. -viscosity and density are examples of intensive properties.
• Extensive Properties -depend on the quantity or size of the matter; their value changes if the size or quantity of matter changes -Ex, length, volume, weight.
• Matter

  Pure Substances Mixtures

  Elements Homogeneous

  Compounds. Heterogeneous
• Based on the no. of kinds of atoms present

  Pure Substances
• Based on the no. of components present

  Mixtures
• Pure Substances -compose of only one component
• Elements are pure substances that are made up of only one kind of atom.
• Compound- are pure substances that are made up of two or more kinds of atoms
• Homogeneous mixture- has a uniform composition and exhibits the same properties in different parts of the mixture.
• Heterogeneous mixture- has a non- uniform composition and its properties vary in different parts of the mixture
• Separation Methods Filtration Distillation Magnetic separation

  Decantation

  Sublimation
• Filtration

  To separate a solid from a liquid in heterogeneo us mixture using a filtering membrane
• Distillation

  To separate a liquid in homogene ous mixture
• Magnetic separation

  To separate a magnetic solid from a heterogene ous mixture
• Decantation

  To separate a solid from a liquid in hetero mixture based on gravity
• Sublimation

  To separate a volatile solid from a non volatile solid
• Mixtures - composed of several components