Date post: | 28-Dec-2015 |
Category: |
Documents |
Upload: | colin-dalton |
View: | 221 times |
Download: | 1 times |
Atoms, Molecules
Atoms are made of 3 parts, ELECTRONS, PROTONS and NEUTRONS– Electrons are negatively charged– Protons are positively charged– Neutrons are neutral (no charge
Protons and neutrons are located in the nucleus of an atom
Electrons are located in the electron could of an atom
Elements are the simplest substance containing the same kind of atoms
Elements are different by the number of protons they have
The six most common elements include:
Carbon, Hydrogen, Oxygen, Phosphorus, Nitrogen and Sulfur
Bonding Basics
Ionic Bonds– Formed when one or more electrons are
transferred from one atom to another
Covalent Bond: Formed when one or more electrons are
shared between atoms
Ion:– These positively and negatively charged
atoms are known as ions
Compounds:– A substance formed by the chemical
combination of two or more elements
Molecules:– The smallest unit of most compounds
How many electrons can he held in the 1st shell? 2 How many electrons can be held in the 2nd shell? 8 How many electrons can be held in the 3rd shell? 8
When an electron is lost, an elements charge becomes more ____________________________
When an electron is gained, an elements charge becomes more __________________________
When an electron is lost, an elements charge becomes more positively
When an electron is gained, an elements charge becomes more negatively
Valence electrons are the electrons in the outermost shell used in bonding of atoms
Water is the only natural substance found in all three states, SOLID, LIQUID and GAS
Water is also a UNIVERSAL SOLVENT: Meaning it dissolves more substances than any other liquid
Water has a unique structure, which is why water molecules are attracted to other water molecule-adhesion. This explains why water drops are in fact, drops
Water becomes less dense when it freezes, which is unusual for liquids
Water has the highest surface tension among common liquids. Surface tension is the ability of a substance to stick to itself
Neutral water has a pH of 7
Structure
The structure of a water molecule:– It has 1 Oxygen atom– It has 2 Hydrogen atoms– They are covalently bonded to each to each other
to create a molecule– Which means they share electrons
Hydrogen Bonds
Hydrogen atoms (with slightly positive charge) in the water molecules form hydrogen bonds with other water molecules (negatively charged oxygen atoms)
They can also happen between hydrogen and other atoms
The Importance of Carbon
Most molecules that make up living things are based on carbon atoms
Carbon can form up 4 covalent bonds Carbon based molecules are molecules
which have one or more carbon to carbon bonds in them
Carbon-based molecules have three basic structures, Chain, Branched and ringed
Structure of Carbon
Many carbon-based molecules have parts that make up bigger molecules.
Each part is called a MonomerMono means one
When monomers are linked together, they form molecules called polymers
Poly means many A polymer can also be a macromolecule
which is a LARGE molecule The monomers that make up a polymer can
all be the same or they can be different
When monomers are linked together, they form molecules called polymers
Poly means many A polymer can also be a macromolecule
which is a LARGE molecule The monomers that make up a polymer can
all be the same or they can be different
Carbohydrates
Fruits and grains both contain large amounts of carbohydrates. Carbohydrates are molecules made up of CARBON, HYDROGEN and OXYGEN
Sugars and starches are both types of carbohydrates. These carbohydrates can be broken down to produce energy in cells
The most basic carbohydrates are simple sugars. Many simple sugars have five or six carbon atoms.
The most familiar type of simple sugar is Glucose
Glucose is a monosaccharide, which means that it contains ONE sugar unit
Fructose and glucose are both sugars that have six carbon atoms. T
The sugar that you might use in the kitchen is made of two sugar molecules bonded together