method that is used to separate the parts of a mixture
the visual output of the chromatography
smaller amount, is dissolved
largest amount, does the dissolving
the movement of a liquid along the surface of a solid caused by the attraction of molecules of the liquid to the molecules of the solid
when an attractive force exists between two unlike materials, such as a liquid and a solid
the mutual attractive force that exists between like molecules
a combination of 2 or more substances that are physically mixed - parts keep their own characteristics
How did water move through the coffee filter?
The movement starts as adhesion, where the water particles are attracted to the paper particles, then as cohesion, where the water trails along the path by a strong attraction between the water molecules themselves.
Activity: Chromatographic Circles
The water moved from the middle of the coffee filter to the edges of the coffee filter first by adhesion then cohesion. As the water moved it separated the color mixture that made up the different black markers. Each marker company uses a different mixture of colors to create black. Some of the circles showed blue, green, and brown colors. Some didn't change at all. The black marker is a solution and the chemicals are the pigments. Some are water soluble and some are not. The further out the water traveled the easier it is to break apart the mixture. This is why you will see the brighter colors towards the outside of the coffee filter.
Properties of Acids
Sour taste i.e. citrus fruit, vinegar
If dissolved in water (aqueous solution) (HCl) added to metals, metal will dissolve and hydrogen gas is released (corrosive)
If aqueous solution (HCl) it will change the color of litmus paper from blue to red
When acids react with bases they form salt and water
Acid will neutralize a base
Electrolytes - will conduct electricity when dissolved in water - has free ions
pH of <7
Properties of Bases
feel slippery i.e. bar of soap
in aqueous solutions will turn litmus from red to blue
react with an acid to form salt and water
electrolyes - has free ions
any substance that is a proton acceptor when it is dissolved in water
will produce hydroxide ions
generally consists of a metal and one or more hydroxide groups
any substance that is a proton donor when it's dissolved in water
positive hydrogen ions quickly surrounded by a water molecule end up with hydronium ion => H30 or H+
a water molecule with an extra hydrogen ion attached to it (H2O + H+=H3O+). It's usually used to determine the acidity of a chemical compound.
consists of an oxygen atom and a hydrogen atom that are covalently bonded to each other. the net charge of a hydroxide ion is -1. In chemical notation, a hydroxide ion is indicated as OH-. Compounds that contain hydroxides usually use ionic bonds.
any ionic compound formed from the reactions between a base and an acid called a neutralization reaction between the hydronium ions and the hydroxide ions. Does not taste bitter or sour, no reaction with litmus, soluble in water
when a strong acid and a strong base solution are mixed, a neutralization reaction occurs, and the products do not have characteristics of either acids or bases. Instead, a neutral salt and water are formed.
pH scale range
a measure of the hydronium ion concentration of a solution
>7 = base
<7 = acid
What is the buffer system?
a weak acid and a weak base that work together to counter shifts in pH
What is carbonic acid?
a weak acid with the formula H2CO3. It is formed in small amounts when carbon dioxide is dissolved in water, and it is usually only found in solution.
What is acid rain?
Rain with a pH of 5.5-4.0. In the atmosphere the sulfuric acid is much stronger than the carbonic acid.
What causes acid rain?
20 million tons of sulfur dioxide is released into the atmosphere due to the burning of fossil fuels, petroleum, coal and natural gas.
What effects does acid rain have?
leaches nutrients and causes trees to go into distress
fish populations can't survive
acid will eat away marble and limestone
yield and quality has declined due to acid rain
Solutions to prevent acid rain:
find other sources of energy such as wind energy
Activity: Making an Indicator
Using red cabbage leaves and rubbing alcohol, we mad an indicator. When mixed in ammonia the solution turned green, and when mixed in vinegar the solution turned pink. All but baking soda which is a base, tap water which is usually neutral and distilled water which is neutral were acids.
Activity: Magic of Your Words
When blowing through the straw into the phenol red and water mixture the accumulation of CO2 from your breath causes a decrease of pH by combining with water to create carbonic acid. Releases hydrogen ions, which react with phenol red causing the mixture to turn yellow.
a type of indicator like litmus
Purposes of carbohydrates
have a structural role - provides a certain shape to a cell
serve as an immediate form of energy which can be transported to other places in the body
Carbohydrates: 3 classes and examples
a. simple sugars
b. 1 sugar unit
c. soluble in water
d. sweet tasting
e. glucose, fructose, galactose, ribose, deoxyribose
a. short chain of only 2 monosaccharides
b. dehydration synthesis - a water molecule is eliminated which allows 2 monosaccharides to combine
c. sucrose, lactose, maltose
a. branching chains of monosaccharides
b. complex carbs
c. cellulose - (walls of plants) main food source for herbivores, termites, fiber for humans, no calories
d. starch - (used to store energy in plants) during digestion turns to glucose when body has more than it needs it turns to glycogen
e. glycogen - storage form of glucose in animal tissue - when used turns to glucose for immediate energy
f. chitin - main structural materials in exoskeletons
greasy, oily hydrocarbon linked together by non-polar covalent bonds, very hydrophobic
energy storage, cell membrane development and serves as a component of hormones and vitamins in the body
Lipids: 4 types and examples
1. true fats
a. solid - saturated fat - get from animals, at room temp. this fat tends to be solid
b. liquid - unsaturated fat - plant fats, liquid at room temp. i.e. olive oil and corn oil
2. phospholipidsa. water insoluble, organic molecule
b. main component of cell membrane (phospholipid bilayer)
c. made up of phosphate group - 2 fatty acid tails and a hydrophilic head
3. steroida. found in cell membranes cholesterol
4. waxesa. fatty acid chains
b. firm yet pliable i.e. cherry covering
c. cuticle (waxy coating) on fruit that helps it preserve water
d. lubricates skin and hair on animals, and coating on duck feathers
A polymer made of monomers known as amino acids - the building blocks for proteins
messenger, transport, structural, enzyme
Structural formula for an amino acid:
central carbon with an R group that determines the type of amino acid
What type of bond joins amino acids together?
peptide bond - small chain covalent bond joins 1 amino acid to another
What are essential amino acids?
20 different amino acids differentiated by R group. R group determines type of amino acid. 8 are essential amino acids - our body cannot make them, we get them from what we eat
molecules that store and transfer info within a cell, originally found in nucleus
DNA - deoxyribonucleic acid
RNA - ribonucleic acid
Nucleic Acid structure
DNA - double helix
RNA - single chain
DNA v. RNA
DNA - double helix
RNA - single chain
DNA - deoxyribose
RNA - ribose
DNA - thymine
RNA - uracil
DNA v. RNA:
Base Pair Rule
DNA Pairings - hydrogen bond between the pairs
AT CG GC TA
AU CG GC UA
Activity: Food Testing
Iodine & Benedict's Reagent solution - What does each of these test for?
Iodine tests for starch
Benedict's Reagent tests for simple sugars
an enzyme found in saliva that breaks down starch and sugars into simple sugars
Top 4 elements that make up the human body:
Oxygen - 65%
Carbon - 18%
Hydrogen - 10%
Nitrogen - 3%
How much of the body's weight is water?
What are the human nutritional requirements?
Carbohydrates - 55-60%
Lipids - 30%
Proteins - 15-20%
20 total proteins - 8 essential
an organic substance, not an energy source, and will help carry out cellular metabolism
13 vitamins - 2 categories
water soluble - need to be replenished daily
fat soluble - stored in fatty tissue, don't need to be replenished as often
an inorganic substance needed for normal growth and maintenance
Incomplete v. Complete Digestive Sytem
Incomplete - a sack-like gut with only one opening, same mouth and anus i.e. flat worm
Complete - one long tube with two openings, mouth on one end and anus on the other, food moves in one direction i.e. human
Function of the digestive system:
To break down food into smaller parts so the body can use them for energy and cell nourishment.
Trace food through the digestive system
Mouth (teeth - mechanical breakdown, saliva - chemical breakdown) food leaves as bolus ->
Pharnyx - a thick-walled muscular tube, opening to the esophagus ->
Esophagus - bolus moves down the esophagus to the stomach ->
Stomach - bolus spends 2-6 hours here - leaves as chyme and moves to the small intestine ->
Small Intestine - chyme moves into the small intestine which is broken up into 3 sections, duodenum, jejunum & ileum. Whatever is left moves on to the large intestine ->
Large Intestine - where the water is removed and reabsorbed to prevent dehydration, feces is formed, moves to the rectum and out the anus ->
Which enzyme digests what:
Salivary amylase & Pepsin
Salivary amylase - breaks down starch and sugars into simple sugars
Pepsin - starts the breakdown of protein, breaks peptide bonds
a soft ball of food that has been broken down in the mouth and will move through the esophagus to the stomach
a semi-fluid mixture of partially digested food after it has been broken down by gastric acid in the stomach and is moving to the small intestine
a wave-like movement of the esophagus that moves the bolus to the stomach
indigestible material in the large intestine
indigestible material of cellulose
finger-like protrusions that line the small intestine and increase the surface area of the small intestine for better absorption of nutrients
smaller finger-like protrusions that line the villi
Where does the actual absorption of nutrients take place?
What is the function of the liver?
Produce and secrete bile that helps digest fats in the small intestine
What is the function of the pancreas?
completes the job of breaking down protein, carbohydrates, and fats using digestive juices of pancreas combined with juices from the intestines
Secretes hormones that affect the level of sugar in the blood
Produces chemicals that neutralize stomach acids that pass from the stomach into the small intestine by using substances in pancreatic juice
What is the function of the gall bladder?
The gall bladder stores bile secreted by the liver
What 3 minerals is the American diet deficient in?