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Title: Lecture on atoms and molecules
Description: This document contains some notes on atoms and molecules A good refresher
Description: This document contains some notes on atoms and molecules A good refresher
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Bio 103 Atoms to Molecules
-Matter is anything that has mass and takes up space
-Elements are the basic building blocks of matter they cannot be broken down by chemical
means
-Over 90% of the human body is made-up of four elements carbon, nitrogen,
oxygen and hydrogen
-An atom is the smallest unit of an element that retains its physical and chemical properties
-Atoms bond together to form molecules
-Neutrons are neutral protons are positive and electrons are negatively charged
-An atomic number is the number of protons
- A mass number is the sum of the number of protons and neutrons
- Atomic mass is the average AMU for all isotopes of the atom
-Isotopes are atoms of the same elements and have the same atomic number but a different
number of neutrons
- Radiomass are unstoppable isotopes; they emit energy called radiation
- Radiation can damage cells and cause cancer
- Molecules are atoms bonded together
- Compounds are molecules made of different atoms, ionic and covalent bonds
-Atoms are most stable when their outer shell is full
-During ionic reactions atoms donate or take on electrons to fill their valence shell
-An ionic bond is the attraction between a positive and negative ion
- Covalent bonds are atoms that share electrons to fill their valence shells
- Double covalent bonds share two pairs of electrons
- Triple covalent bonds share three pairs of electrons
- Water is a polar molecule
- A hydrogen bond is the attraction between a slightly positive hydrogen to a slightly negative
oxygen or nitrogen
Title: Lecture on atoms and molecules
Description: This document contains some notes on atoms and molecules A good refresher
Description: This document contains some notes on atoms and molecules A good refresher