Chemistry & Electrical Current Flashcards
What is chemistry?
The science that deals with composition, structure and properties of matter and how matter changes under different conditions.
What are the two branches of chemistry?
- Organic
2. Inorganic
What is organic chemistry?
-the study of substances that contain an element of carbon.
What do all living things contain?
All living things (plants and animals) contain carbon
What makes organic substances burn?
- Organic substances are flammable and will burn
- gasoline, plastics, synthetic fabrics, pesticides, and fertilizers are all organic substances
- carbon is flammable
What is inorganic chemistry?
Dealing with compounds that do not contain the element of carbon but may contain the element hydrogen
Are inorganic substances flammable?
-No (they do not have carbon)
Are inorganic substances “alive”?
They are not and never were considered alive
What are examples of inorganic substances?
Metals, minerals, glass, water, air.
What is matter?
Any substance that occupies space and has a mass (weight).
What two properties do all types of matter have?
-physical and chemical properties
All matter exists in either of these three forms:
- Solid
- liquid
- gas
What is an element?
- is the simplest form of chemical matter
- cannot be broken down into smaller substances without loss of identity
How many naturally occurring “elements” are there?
-about 90
What are Atoms?
Particles from which all matter is composed
What is the smallest particle of an element?
-an ATOM is the smallest part of en element that still retains properties of that element
How do atoms vary or change between each element?
-the atoms of each element are different in structure
Atoms consist of smaller particles called:
Protons- positively charges
Neutrons- neutrally charged
Electrons- negatively charged
Describe the number of protons in an atom compared to the number of electrons:
-the number of protons in an atom is EQUAL to the number of electrons
An atom is FORMED by:
-a nucleus and cortex
In a “happy” atom: the number of protons in the _________equals the number of electrons in the_________
- nucleus
- cortex
Why is an Atom considered to be “electrically neutral”?
-because the number of positive protons equals the number of negative electrons
As is in the following diagram:
What is a Molecule?
-a Molecule is formed by chemically joining two or more atoms
What is a water molecule?
-formed from two hydrogen atoms and one oxygen atom, existing together in harmony (H2O)