Unit 0 Flashcards
What is Chemistry?
Chemistry is the study of matter, its composition and properties and the changes they undergo
What is a Substance?
Something that has a definite composition
What is a Composition?
A description of matter in terms of the types and amount of simpler substance that make it up
What are Properties?
Characteristics of the substance that give it its unique identity
What are examples of Physical Properties?
Density
Melting point
Hardness
Electrical Conductivity
What do Chemical Properties describe?
How a substance changes or interacts with other substances
What are examples of Chemical Properties?
Corrosiveness
Flammability
Reactivity with Acids
When do Chemical changes occur?
When a substance is converted to other substances
What changes in a chemical change?
The composition
What can cause a substance to change state?
Temperature or Pressure
What is Energy?
The ability to do work
What is Potential Energy?
Energy possessed due to position of an object relative to other object
What is Kinetic Energy?
Energy Possessed due to motion of an object
What can Matter be classified into?
Substances and Mixtures
What can Substances be classified into?
Elements and Compounds
What do Elements consist of?
One kind of atom
What do Compounds consist of?
Two or more elements chemically bonded together into molecules or extended structures
What are mixtues?
(Heterogenous or homogeneous) two or more substances whose proportions can vary
How much does an electron weigh?
amu=1.66x10^-24 g
What is the Atomic Notation
^A down Z by X
What does A represent?
Mass Number
What does Z represent?
Atomic Number
What does X represent?
Chemical Symbol
What is the mass of an atom expressed relative to?
Carbon 12 atom which is equal to 12 amu
