Chemistry of Life Chapter 2 MATTER Matter anything

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Chemistry of Life Chapter 2

Chemistry of Life Chapter 2

- MATTER – Matter – anything that takes up space and has mass •

- MATTER – Matter – anything that takes up space and has mass • Everything in the universe is made of matter. • Chemical changes in matter is essential to all life processes. •

Elements – the purest substances • Examples: Carbon Hydrogen Oxygen Nitrogen Phosphorous CHON-P Atoms:

Elements – the purest substances • Examples: Carbon Hydrogen Oxygen Nitrogen Phosphorous CHON-P Atoms: The simplest particle of an element that retains all of the properties of that element.

Structure of an atom • Inside the Nucleus: Protons – positive electrical charge Neutrons

Structure of an atom • Inside the Nucleus: Protons – positive electrical charge Neutrons – no electrical charge **The atomic number of an element is always the same as the number of protons it has. • Outside the Nucleus: Electrons – negative electrical charge ** Electrons rotate around the nucleus on different shells or energy levels. • The first shell or level holds 2 electrons • The outer shells hold 8 electrons

Atom Model Brainpophttp: //www. brainpop. com/science/mat terandchemistry/atoms/preview. weml

Atom Model Brainpophttp: //www. brainpop. com/science/mat terandchemistry/atoms/preview. weml

ATOMS FAMILY 1 st Verse: They’re tiny and they’re teeny, Much smaller than a

ATOMS FAMILY 1 st Verse: They’re tiny and they’re teeny, Much smaller than a beany, They never can be seeny, The Atoms Family. Chorus 3 rd Verse: Neutrons can be found, Where protons hang around; Electrons they surround The Atoms Family. Chorus 2 nd Verse: Together they make gases, And liquid like molasses, And all the solid masses, The Atoms Family Chorus: They are so small. (snap, snap) They’re round like a ball. (snap, snap) They make up the air. They’re everywhere. Can’t see them at all. (snap, snap)

VERY IMPORTANT !!!!!! • All atoms want to be happy (stable) • In order

VERY IMPORTANT !!!!!! • All atoms want to be happy (stable) • In order to be stable their outer shell must be full. • Using the carbon atom as an example with 4 electrons in the outer shell, how many more electrons does it need to be stable? • Answer 4 • So it is capable of making 4 bonds with other elements.

COMPOUNDS • A pure substance made up of two or more elements • Example

COMPOUNDS • A pure substance made up of two or more elements • Example – Water • H 2 O • Two Hydrogen atoms and 1 Oxygen atom

CHEMICAL BONDS • Elements undergo chemical reactions, combining in ways that cause their atoms

CHEMICAL BONDS • Elements undergo chemical reactions, combining in ways that cause their atoms to become stable • COVALENT BONDS Two atoms share one or more pairs of electrons *Molecule – the simplest part of a substance that can exist in a free state. e. g. 2 hydrogen atoms = 1 hydrogen gas molecule

IONIC BONDS Electrons are transferred from one atom to another Example Sodium + Chlorine

IONIC BONDS Electrons are transferred from one atom to another Example Sodium + Chlorine = Sodium Chloride is table salt (Na. Cl) Sodium 11 Protons, 11 electrons. Gives one electron to Chlorine. Left with 11 Protons, 10 electrons. What is the net charge?

Chlorine: 17 protons, 17 electrons Outer shell has only 7 electrons – not stable

Chlorine: 17 protons, 17 electrons Outer shell has only 7 electrons – not stable When it gains an electron from sodium it becomes stable but gains an electrical charge. Is it positive or negative? Answer: Negative

 • Ions: atoms or molecules that have an electrical charge • What happens

• Ions: atoms or molecules that have an electrical charge • What happens when you put a positively charged atom and a negatively charged atom together? • Answer: They are attracted to each other And since they are both ions, they form an Ionic Bond. http: //www. brainpop. com/science/matterandche mistry/chemicalbonds/

REDOX REACTIONS • AKA – Reduction – Oxidations Reactions • Reactions that involve a

REDOX REACTIONS • AKA – Reduction – Oxidations Reactions • Reactions that involve a transfer of electrons • Many of the energy transfers in living things involve redox reactions (transfer of electrons) • Redox reactions always occur together. • One atom gains electrons, one loses electrons

HOW TO REMEMBER • What is a typical lion’s name and what sound does

HOW TO REMEMBER • What is a typical lion’s name and what sound does he make? • LEO – GER • Lose Electrons Oxidation • Gain Electrons Reduction

Where is water found? • Ocean • Cells • Tissues • Blood • Moist

Where is water found? • Ocean • Cells • Tissues • Blood • Moist soil

What are solutions • • Of the following items, identify the Solution Solute Solvent

What are solutions • • Of the following items, identify the Solution Solute Solvent • sugar + water = sugar water

 • Sugar is the solute – a solute is the substance dissolved in

• Sugar is the solute – a solute is the substance dissolved in the solution. • Water is the solvent – a solvent is the substance in which the solute is dissolved. • Sugar water is the solution – a solution is one or more substances distributed evenly in another substance.

How do you measure concentration? • The more solute you have in a solution,

How do you measure concentration? • The more solute you have in a solution, the greater the concentration of that solute. • If one solution is 5% salt and 95% water and the other is 20% salt and 80% water, which has a greater concentration of salt?

What is saturation? • If a solution is saturated, no more solute can be

What is saturation? • If a solution is saturated, no more solute can be dissolved

BLOOD Plasma – the liquid part of blood Solutes in blood – • molecules-

BLOOD Plasma – the liquid part of blood Solutes in blood – • molecules- such as glucose (sugar), protein, and fats • gases – such as oxygen, carbon dioxide • ions – such as sodium, potassium, chlorine

p. H scale • When the water molecule splits apart, called dissociation, it creates

p. H scale • When the water molecule splits apart, called dissociation, it creates 2 ions: a hydroxide and a hydronium ion. • ACIDS are the result of a greater amount of hydronium ions in a solution • BASES are the result of a greater amount of hydroxide ions in a solution

ACIDS AND BASES • Acids have a sour taste, and can be corrosive to

ACIDS AND BASES • Acids have a sour taste, and can be corrosive to some materials • Bases have a bitter taste, and tend to be slippery. Some soaps are made from bases and oils. ALKALINE is another term used to describe a basic solution.

MEASURING p. H • A p. H scale is used to measure acids and

MEASURING p. H • A p. H scale is used to measure acids and bases. • It ranges from 0 to 14, with 0 being very acidic, and 14 being very basic. A p. H of 7 would be neutral, meaning the same amount of hydroxide and hydronium ions.

BUFFERS • A Buffer is a chemical substance that neutralizes acids and bases. It

BUFFERS • A Buffer is a chemical substance that neutralizes acids and bases. It makes them less strong. • Aqueous Solution – any solution where the solvent is water

WHY IS p. H important? • Enzymes in your body will only work within

WHY IS p. H important? • Enzymes in your body will only work within a narrow range of p. H. If enzymes can’t do their job, lots of chemical reactions necessary for life cannot take place.

EXAMPLES OF p. H • Acids: vinegar, stomach acid, urine • Bases: ammonia, milk

EXAMPLES OF p. H • Acids: vinegar, stomach acid, urine • Bases: ammonia, milk of magnesia • Neutral: water, blood, intestinal fluid

 • http: //www. brainpop. com/science/matterandchemistry/phsc ale/

• http: //www. brainpop. com/science/matterandchemistry/phsc ale/