Chemistry of Life

The universe is composed of either _______ or _______. matter energy

mass space Matter is anything that has _______ and takes up ________. What are some examples of matter? trees air bear rocks soil water

All matter is made up of ________. atoms An atom is the smallest unit of matter.

Although there is a huge variety of matter on earth, all matter is composed of atoms, and all atoms share the same basic structure.

protons neutrons electrons protons electrons neutrons Atoms consist of three types of smaller particles: _______________ are positively charged ( ) _______________ are neutral (no charge, ) _______________ are negatively charged ( )   protons +1 neutrons electrons -1 protons electrons neutrons

  +1 What is the charge of a proton? _____ What is the charge of a neutron? _____ -1 What is the charge of a electron? _____

nucleus protons neutrons nucleus The area in the center of the atom is called the ________ and it contains ________ and _________. nucleus protons neutrons nucleus

Are all atoms identical Are all atoms identical? ______ How does one atom differ from another atom? ____________________________ no In the number of protons and electrons

Hydrogen atom Helium atom 1 # protons = ___ 2 # protons = ____ # neutrons = ____ 2 # neutrons = ____ 1 # electrons = ____ 2 # electrons = ____ overall charge = __________ +2 + (-2) = 0 overall charge = __________ +1 + (-1) = 0

3 3 4 + = How many protons in this atom? _____ How many electrons How many neutrons in this atom? _____ 4 What is the overall charge of this atom? ______________ + = (+3) (-3)

Atoms are neutral when they have the same number protons as electrons. number of protons = number of electrons How many protons in this atom? _____ 6 How many electrons in this atom? _____ + + + + 6 + + What is the overall charge of this atom? _____

Element Key 6 C Carbon 12.011 # of protons Symbol of element Name of Element Atomic mass

carbon, C An atom with 6 proton is an atom of ___________. An atom with 7 protons is an atom of __________. An atom with 8 protons is an atom of __________. An atom with 20 protons is an atom of __________. An atom with 47 protons is an atom of _________. An atom with 79 protons is an atom of _________. nitrogen, N oxygen, O calcium, Ca silver, Ag gold, Au

Matter can be composed of an element, a compound, or a mixture. Element – a pure substance made of one type of atom, and it cannot be broken down. Aluminum, Al

Helium gas What is helium? An element He He He He He He He He He He He

Diamond What are diamonds composed of ? Billions of carbon atoms!!! C

There are 109 elements. What makes one element different from another element?

The atoms of different elements are different! Theirs atoms! The atoms of different elements are different! A hydrogen atom A carbon atom

How are these atoms different? The atoms of differ in the number of protons, neutrons, and electrons. A hydrogen atom A carbon atom

There are 109 different atoms.

There are 109 elements on Earth, but only about 25 are found in organisms.

Elements found in living organisms: Oxygen Carbon Hydrogen Nitrogen Calcium Phosphorus Potassium Sulfur Chlorine Sodium Magnesium Iodine Fluorine Iron Bromine Aluminum Silicon Manganese

96% of the mass of a human is made of only 4 elements – carbon, 96% of the mass of a human is made of only 4 elements – carbon, hydrogen, oxygen, nitrogen.

You are mostly composed of: hydrogen carbon nitrogen oxygen

Composition of the Human Body 65% oxygen. 1. 5% calcium Composition of the Human Body 65% oxygen 1.5% calcium 0.2% potassium 18% carbon 1.2% phosphorus 0.1% sodium 10% hydrogen 0.2% sulfur and other elements 3% nitrogen  

Most elements do not exist alone. Elements combine to form compounds. Compound - a pure substance that is composed of atoms of two or more different elements joined by chemical bonds. O H H

O WATER - - - H2O H H Chemical formula? one atom of oxygen Chemical bond O H H one atom of oxygen Water is composed of __________________ and ____________________ joined by _______________ two atoms of hydrogen chemical bonds.

O C O CARBON DIOXIDE - - - CO2 Chemical formula? one atom of carbon Double bonds one atom of carbon CO2 is composed of __________________ and ___________________ joined by _______________ two atoms of oxygen chemical bonds.

H N H H AMMONIA - - - NH3 Chemical formula? one atom of nitrogen Ammonia is composed of ___________________ and ______________________ joined by _______________ one atom of nitrogen three atoms of hydrogen chemical bonds.

C12H22O11 table sugar (sucrose) 11 atoms 12 atoms of oxygen of carbon of hydrogen

O H H Water, H2O The elements that make up a compound     The elements that make up a compound are held together by chemical bonds. A chemical bond is a force of attraction between two atoms. Chemical bond Chemical bond O  Water, H2O H H

There are two types of chemical bonds: Covalent bond Ionic bond

O Covalent bond Covalent bond – chemical bond between atoms     Covalent bond – chemical bond between atoms in which electrons are shared. Covalent bond O H H

Cl- Ionic bond (2) Ionic bond – chemical bond between atoms     (2) Ionic bond – chemical bond between atoms in which electrons are transferred to other atom. Ionic bond Cl- Na+

    What is an element? Only one type of atom

ELEMENT One type of atom Only red atoms Only blue atoms

    What is a compound? Two or more different elements

COMPOUND Two or more different atoms chemically attached Two different atoms Three different atoms

Element or compound? element compound compound element compound