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Unit 5 BiochemistryObjectives

Topic 1: Atomic Structure

o Identify the three subatomic particles found in atoms

o Describe the two main types of chemical bonds

Topic 2: The Periodic Table and its elements

o Explain the structure of the Periodic Table based on atomic structure

Topic 3: Mixtures: Suspensions & Solutions

o Differentiate between mixtures, solutions and suspensions

Topic 4: Water

o Explain structure of a water molecule and why it is polar covalent

o Identify the properties of water that are important to life

Topic 5: Acids, Bases and pH

o Describe how the concentration of hydrogen ions determines the pH

Topic 6: Organic Compounds

o Identify the 6 major biological elements and draw their Bohr models.

o Describe the structure and function of proteins, lipids and carbohydrates and

nucleic acids.

Topic 7: Enzymes

o Explain why enzymes are important to living things

o Describe how enzymes function (enzyme-substrate complex)

o Identify how temperature and pH affects the rate of enzyme activity.

I mportant Dates: 11/20 Vocabulary Due

12/1 Quiz 1 Vocabulary, atomic structure and properties of water

12/11 Quiz 2 Biochemistry Organic Compounds

12/5 LAB – Organic Compounds

12/7 LAB – Enzymes

12/13 Unit Test

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VOCABULARY

Word What it looks like to me

Definition

Ionic bond

Covalent bond

Mixture

Solution

Solute

Solvent

Suspension

4

Cohesion

Adhesion

Acid

Base

Buffer

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Word What it looks like to me DefinitionMonomer

Polymer

Carbohydrate

Monosaccharide Disaccharide Polysaccharide

Lipid

Protein

Amino acid

Dehydration Synthesis

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Hydrolysis

Enzyme

Substrate

Catalyst

Denature

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Atomic Structure

Atom is the basic unit of matter which are incredibly small – 100 million would be about the width of your pinkie!

It is made up of subatomic particles called protons, neutrons and electrons.

Particle Mass Location ChargeNeutron

1 AMU Nucleus No charge

Proton1 AMU Nucleus Positive charge

Electron0 AMU Outer Shell Negative charge

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Periodic Block

Bohr Models

Bohr Models are pictures to represent atomic structure. Bohr said that electrons move in specific

energy levels. The further electrons are located away from the nucleus, the more energy it is said to

have.

Energy Level Max # of Electrons

1 2

2 8

3 8

Valence Electron – Electrons in the last energy level. The valance electrons will determine

whether an atom will bond or not!

Atomic Mass = protons + neutrons

Atomic Symbol

Atomic Name

Atomic number = # of protons

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Create a Bohr Model forSodium – (Na) Atomic Number 11 Atomic Mass 22

11

Na

Sodium

22

11 P+11 N

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The Periodic Table

Periods – Run horizontally or across the periodic table.

Groups – Run vertically or down the periodic table.

Groups have the same number of valance electrons in the outer shell

Group 18 is call the Noble Gases because complete outer shell

Valance 4 5 6 N

OBLE GASES

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Chemical Bonding

The joining of two or more elements to form a new compound.

Elements combine to form compounds by a process called chemical bonding.

The formation of a chemical bond involves either the transfer of electrons from one atom to another,

OR the sharing of electrons between atoms.

Atoms tend to fill partially filled valance shells or empty partially filled valance shells.

This drives chemical reactions to create chemical bonds!

1 - Ionic Bonds – Formed when valance electrons are transferred from one atom to another.

Ions – are atoms that have gained or lost electrons and become either positive lost electron)

or negative (gained electron).

Example: Sodium Chloride Na+Cl-

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2 - Covalent Bonds – A type of bond that occurs when electrons are equally shared between atoms to form compound Example: Methane CH4

H = electrons in outer shell

C = electrons

Shared electrons

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Bohr Model WorksheetUse your notes and the periodic table to help you complete the Bohr models.

a. How many electrons can each shell hold? 1st = 2 2nd = 8 3rd = 8

Element Atomic #

Atomic Mass Protons Neutrons Electrons Bohr Model

Carbon 6 12 6 6 6

Hydrogen 1 1 1 0 1

Nitrogen 7 14 7 7 7

6P+6N

P+

7P+7N

8P+8N

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Oxygen 8 16 8 8 8

Properties of Water

Water is POLAR COVALENT: leads to many interesting properties of water…

A pair of electrons share unequally by 2 atoms.

Oxygen has stronger “attraction” for the electrons than hydrogen (electronegativity)This makes water polar, meaning there is a positive pole (H+) and a negative pole (O-). Example: water = H2O

Diagram:

H2O molecules form hydrogen bonds with each other H+ is attracted to O- which creates a hydrogen bonds and allows for unusual properties of water.

Unusual Properties of Water – because of HYDROGEN BONDS

1. Cohesion and Adhesion = Surface Tension and Capillary Action

8 P+8 N

Water is polar covalent.

Oxygen has electrons more than hydrogen so it is more electronegative

Hydrogen is more positive

1 P+N

0 -

H+H+

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High Surface Tension =

Hydrogen bonds hold water molecules together so tightly that the water’s surface acts like a solid,

this is also called cohesion (attraction between the same substances).

EXAMPLE: Capillary ActionGlass or other polar substances allow the polar water molecules to spontaneously “climb” the walls.

An example in nature is transpiration.Cohesion is how water sticks to itself. Example: surface tension Adhesion is how water sticks to other surfaces. Example: meniscusEXAMPLE: Transpiration or Meniscus

2. Good Solvent = hydrophilic (loves = water vs. hydrophobic (repels = water

Water is an excellent solvent because the polarity of water molecules can interact with so many

substances.

Solvents dissolve solutes creating solutions(water) (salt) (salt water)EXAMPLE:

Hydrophillic polar Attracted Example: saltHydrophobic non-polar not attracted Example: oil

3. Low density as a solid = Ice floats!

Ice is less dense than water and therefore it floats on top of liquid water.

H+ bonds form crystals as they freeze which creates air space and lowers the density.

This is important because

1. Surface ice insulates the water below. 2. This creates seasonal turnover as water freeze and thaws .

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4. High Specific Heat Capacity = Water stores heat

H20 resists change in temperature

Water can absorb a lot of energy without having its temperature increase by very much. Water

molecules are held together so strongly by their hydrogen bonds than the amount of heat required

to get the molecules moving fast enough to heat up is a lot.

H20 modules temperatures on Earth

EXAMPLE: water to boil takes a lot of energy

5. High Heat of Vaporization/Fusion = Heats & Cools slowly

It takes a lot of energy to evaporate water or freeze water. Why is this important to living organisms? Allows organism to maintain homeostasis and adjust

to seasonal temperature change

EXAMPLE:

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Mixtures, Solutions and Suspensions

What are Mixtures?

Mixtures - materials composed of one or more elements or compounds that are physically mixed together but not chemically combined. Examples: Pizza toppings

solutionsSolvent – Substance that disolves the solute(You will have more of this item)

Example: water

Solute – Substance that IS dissolved in a solvent to make a solution (You will have less of this item)

Example: salt

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Acids, Bases, Buffers - pH Scale

A water molecule (H20) can react to form __________________ ions _____ and ___________________ ions _______

Equation:

pH Scale: Indicates the concentration of H+ ions and OH- ions in a solution. Ranging from 0 to 14 a

pH of 7 indicates and equal concentration of Hydrogen ions and Hydroxide ions..

Neutral, Acid or Base

if [H+] = [-OH], water is neutral pH = 7

if [H+] > [-OH], water is acidic pH = 0-7

if [H+] < [-OH], water is basic pH = 7-14

Neutral

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Buffers: weak acids or bases that can react with strong acids or bases to prevent changes in pH.

For example, we must maintain a stable blood pH. If we aren't able to do this, chemical reactions in

our body's cells will be negatively affected, cells could be damaged or the organism could die.

Control pH by buffers reservoir of H+

donate H+ when [H+] falls

absorb H+ when [H+] rises

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Biochemistry and Organic CompoundsChapter 2 (Sections 3 and 4)

The study of all molecules that contain bonds with carbon atoms.

Why Carbon?

Carbon has a valance of 4. This means that it can bond with many different elements to form chains

or hydrocarbons

Draw a Bohr model of Carbon

Macromolecules – BIG = MACRO

Macromolecules are polymers “giant molecules”, that are formed by the joining of monomers of

small molecules. Mono = 1

6 P+6 N

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Monomers are joined to form polymers in a process called dehydration synthesis. (take away H2O) Example: Photosynthesis

Polymers are

broken down into monomers by a process called hydrolysis (add H2O)

Example: Cellular Respiration is using glucose for energy

Polymer monomer monomer

Inorganic do not contain carbon and hydrogen

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MacromoleculesAtomic # 6 1 7 8 15

C H O N P SV 4 V1 V5 V2 VB 4 B1 B3 B6 B8

Valence # 8 2 8 8atoms or bonds within molecules that are responsible for the characteristic chemical reaction of those molecules. The same functional group will undergo the same or similar chemical reaction(s) regardless of the size of the molecule it is a part of.

Alcohol: OH

R -- Alcohol

Carboxylic Acid: COOH

R -- Acid

Amine: NH2

R --- Amine

Aldehyde: CHO or COH

R -- Aldehyde

O - H

H

N H

H

N H

OC OH

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Two-Dimensional Structural Formulas for Compounds: A structural formula shows you how the various atoms are bonded. When creating a structural formula for a compound always read the chemical formula from left to right.

Chemical Formula Structural Formula

C4H9OH H H H H I I I I H – C – C -- C- C -- Alcohol I I I I H H H H

C2H5COOH H H I I H – C – C -- m Acid bonds will always I I be bent H H

NH2CH2COOH

-- C --

CH3COH H I H – C – Aldehyde I H

O

C H

O - H

OC OH

H

N H

O

C OH

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Organic CompoundsElements Chemical Properties Function(s)

Lipidspage 46

Test to Identify:

Brown Paper Test

C

H

O

Short Hand Drawing

Monomer: 1 Glycerol 3 Fatty Acids

1.Store energy (long term energy)2. Cell Membrane3.Steroids – Chemical messenger4. Insulation

Carbohydratespage 45Test to Identify:

Iodinefor starch

Benedicts solution for simple sugars

C

H

O

1: 2: 1C H O

Short Hand Drawing

Monomer: Glucose

1. need quick energy2. structure (plans, fungi & arthropods) cellulose Chitin3. cell membrane channelsMonosaccharide one sugar or glucoseDisaccharide two glucosePolysaccharide many glucose

Proteinspage 47

Test to Identify:Biuret ReagentPink or purple = protein

C

H

O

N

some S

Short Hand Drawing AA AA

Monomer: are Amino Acids

1. Cell Products enzymes hormones antibodies

2. Cell repair + Growth Pipepide = 2 AA Polypeptide = many AA

Nucleic Acidpage 291Macromolecules

C

H

N

O

P

Short Hand Drawing

Monomer: Nucleic Acids A– C – T - C

1. Genetic Information2. Transmits Hereditary Information

DNA / RNA

G

FA

FA

FA

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LAB Organic CompoundsBACKGROUNDThe foods you eat are made of organic compounds. In this lab we will be testing for those compounds in the form of starch, sugar, protein and fat in a few common food sources. We will use Iodine, Biurets reagent, Benedicts solution and brown paper to test the foods.

MATERIALS Food Substances:

8 test tubes appleTest-tube rack melted butterStirring rod raw egg whiteMasking tape raw fishTest-tube holder raw potatoSAFETY GOGGLES raw spinachTesting Agents: vegetable oil & distilled water

IodineBiuret reagentBenedict’s solution

PROCEDURE Read all the directions for EACH SECTION FIRST before you begin.

1. Wear your SAFETY GOGGLES THE ENTIRE TIME.2. ALL FOOD should go into the TRASH CAN.

Put 8 test tubes in your test-tube rack. Label each test tube by putting masking tape near the top

edge of the test tube. Use a pencil to write one of the seven food substances on each label. Mark the

eighth label water. The water is your control

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PREDICTION – On a scale of 0-4 (4 is the most) how much do you think each test food has of each organic compound?

FOOD STARCH SUGAR LIPIDS PROTEINAPPLE

BUTTEREGG WHITEFISH Bread

POTATOSPINACH

VEGETABLE OILWATER

PART I: TESTING FOR LIPIDS (brown paper towel or paper bag)

1. Place a small amount of each food on the brown paper. 2. Move on to Test II then return to complete steps 3-4.3. Remove the food from the paper. 4. Observe and compare/contrast the translucence of the place on the paper of each

food substance by holding up the paper to the light. Record the information, in order of translucence (0-4) in your data chart. The food which contains the most lipids should be recorded as 4.

PART II: Testing for Carbohydrates (STARCH – Iodine)

1. Place a small amount of each food in the test tube with the matching label. Add 3-4 drops of iodine to each test tube.

2. Starch is one form of carbohydrate. If the substance in your test tube contains starch, it will turn a blue-black color when it mixes with the iodine solution.

3. Observe the contents of your test tubes and Record the amount of starch present (0 – 4) in your data chart. The food which contains the most starch should be recorded as 4.

4. Empty into the TRASH and wash each test tube and return it to the rack.

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PART III: Testing for Carbohydrates (SUGAR – Benedict’s Solution)CAUTION: Benedict’s solution is poisonous. Do not get any in your mouth and do not swallow any!

1. Place a small amount of each food in the test tube with the matching label. Add 8-10 drops of Benedict's solution to each test tube.

2. Use a test-tube holder to carefully place the test tubes in the hot water bath your teacher has prepared. Heat the test tubes for 2. CAUTION: Use a test-tube holder to handle hot test tubes. Point the open end of a test tube away from yourself and others.

3. Use a test -tube holder to return the hot test tubes to the test-tube rack. If the substance in your test tube contains sugar, Benedict's solution will change color.

Table 1: Appearance of Substance after Adding Benedict's SolutionAmount of

Sugar in Food0

none1

trace2

little sugar3

some sugar4

much sugarColor blue blue/green green yellow orange/red

4. Observe your test tubes (holding a piece of white paper behind the test tube). Record the amount of sugar present, in your data table.

5. Empty into the TRASH and wash each test tube and return it to the rack.

PART IV: TESTING FOR PROTEIN – Biuret Reagent

CAUTION: Biuret reagent can burn your skin. Wash off spills and splashes immediately with plenty of water while calling to your teacher.

1. Place a small amount of each food in the test tube with the matching label. Use a medicine dropper to carefully add 10 drops of Biuret reagent to each test tube.

2. Observe the contents of each test tube (using white paper as a background). If the food contains proteins, it will turn a pinkish purple. Record the amount (0-4) of protein for each food substance in your data table. The food which contains the most protein should be recorded as 4.

3. Empty the test tubes and clean them thoroughly. Set up your lab station exactly as you found it ready for the next class.

4. Wash your hands thoroughly before leaving the classroom.

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LAB Organic Compounds

NAME __________________Block ____ Score _____/20Complete the table below using the scale of 0-4 as you complete the lab.

I II III IVFOOD News Print Iodine Benedicts Biuret Reagent

Testing for: Lipids Starch Sugar Protein

APPLE

BUTTER

EGG WHITE

FISH

POTATO

SPINACH

VEGETABLE OIL

WATER

1. Which organic compound is most common in foods that come from plants?

Which organic compound is most common in foods that come from animals?

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2. Does water contain any of the organic compounds you tested? Explain why water was used as the control.

3. If you wanted to reduce the amount of fat in your diet, what foods would you avoid? Why should we not completely eliminate fats in our diet?

4. Which foods tested would your body use for a quick burst of energy? For energy when no carbohydrates are available? For rebuilding cells in your organs?

5. Write about 2 things that you have learned about organic chemistry and explain how it applies to your life every day. Be sure to include vocabulary and information from your notes that you have learned. You can use the back of this sheet or type your answer.

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LAB Organic Compounds

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EnzymesSome chemical reactions that make life possible are too slow or have activation

energies that are too high and therefore are useless or dangerous for living tissue.

Enzymes play an essential role in regulating chemical pathways, making material s that

cells need, releasing energy, and transferring information.

Enzymes are proteins (polymers of amino acids) that act as biological catalysts (they

speed up processes in our cells)

A catalyst is a substance that speeds up the rate of a chemical reaction by lowering the

activation energy. See figures 2-20 in your text.

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Example: Our bodies naturally produce hydrogen peroxide, a toxic chemical made of water and oxygen. The enzyme catalase speeds up the reaction to break this chemical down into water and oxygen.

2H2O2 2H20 + O2

How do enzymes do their job?Enzymes are very specific and form what is referred to as an enzyme–substrate

complex. See Figure 2-21 in your text.

This enzyme-substrate complex can also be referred to, as a lock and key because

enzymes are very specific about which substrate will fit into the activation site.

What affects enzyme reaction rate?Enzymes work best at an optimal pH and temperature. A change in either of these

variables breaks the bonds of the protein and therefore changes the structure of the

enzyme. This is called denaturing the enzyme because the enzyme is no longer in its

natural form. If the enzyme is denatured the substrate will not fit and the chemical

reaction cannot take place.

Enzymes

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Some chemical reactions that make life possible are too slow or have activation energies that are too high and therefore are useless or dangerous for living tissue.

Enzymes play an essential role in regulating chemical pathways by

1)making materials that cells need 2) releasing energy 3) transferring information.

What are enzymes and what do they do? Proteins – biological catalysts that speed up reactions.

A catalyst is a substance that speeds up rate of chemical reaction by lowering the activation energy See figure 2-20 in your text.

Example: Our bodies naturally produce hydrogen peroxide, a toxic chemical made of

water and oxygen. The enzyme catalase speeds up the reaction to break this

chemical down into water and oxygen.Write the equation:

H2O2 = H2O + O2

How do enzymes do their job?Lock and Key – Enzyme substrate complex enzymes break substrates into products.Draw and label the enzyme substrate complexWhat affects enzyme reaction rate?

Active Site

Enzyme

Enzyme Substrate Complex Enzyme

Products

Substrate

+

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Catalase ENZYME LabHow do enzymes work in living tissues?

OBJECTIVES- After lab can you: Explain why enzymes are important to living things?

Describe how enzymes function?

Identify how temperature and pH affects the rate of enzyme activity?

Introduction (Read and highlight or underline)

What would happen to your cells if they made a poisonous chemical? Do you think that

your cells would die? In fact, your cells are always making poisonous chemicals. They

do not die because your cells use enzymes to break down these poisonous chemicals

into harmless substances. Enzymes are proteins that speed up the rate of reactions

that would otherwise happen too slowly to maintain life. The enzymes are not altered

by the reaction. You have hundreds of different enzymes in each of your cells. Each of

these enzymes is responsible for one reaction that occurs in the cells.

In this lab, you will study an enzyme that is found in the cells of many living

tissues. The name of the enzyme is catalase; it speeds up a reaction, which breaks

down hydrogen peroxide, a toxic chemical made of – water and oxygen. The reaction is

as follows:

2H2O2 2H2O + O2

REACTANT PRODUCTS

This reaction is important to cells because hydrogen peroxide (H2O2) is produced as a

byproduct of many normal cellular reactions. If the cell doesn’t break down the

hydrogen peroxide, they would be poisoned and die.

In this lab, you will study the catalase found in liver cells. You will be using

chicken or beef liver that your teacher purchased in the supermarket. It might seem

strange to use dead cells to study the function of enzymes but is possible because

when a cell dies, the enzymes remain intact and active several weeks, as long as the

tissue is kept refrigerated.

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Pre-Lab Questions – ANSWER ALL Questions on the ANSWER SHEET1. What are enzymes and why are they important to living organisms?2. What is the enzyme we are studying in this lab and where is it found in

animals?3. What are the reactants and what are the products we will see in this lab?

Prelab Preparation

Review your notes about enzymes. Recall that the substrate is a molecule that the

enzyme breaks apart, and the products are the molecules produced by that reaction.

Review why enzymes are reusable.

Under certain conditions enzymes are denatured. An enzyme is denatured when

the protein molecule loses its proper shape and cannot function. Some things that can

denature an enzyme are high temperatures, extremes of pH, heavy metals, and alcohol.

In this lab we will be using acid and boiling water to denature the enzyme catalase.

Part 1: Normal Catalase Activity

NOTE: Be sure to clean your stirring rod (and your test tubes, if necessary) between

steps.

A. Place 2 mL of the 3% hydrogen peroxide solution into a clean test tube.

4. Is the hydrogen peroxide bubbling?

B. Using forceps and scissors cut a small piece of liver and add it to the test tube.

Gently push it into the hydrogen peroxide with a stirring rod.

5. Observe the bubbles; what gas is being released?

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Throughout this investigation you will estimate the rate of reaction (how rapidly the

solution bubbles) on a scale of 0-5 (0=no reaction, 1=slow,…5=very fast). Assume that

the reaction in step B proceeded at a rate of “4” and record the speed in a Chart I.

C. Recall that a reaction that absorbs heat is endothermic; a reaction that gives off

heat is exothermic. Now, feel the temperature of the test tubes with your hand.

6. Has it gotten warmer or cooler? Is the reaction endothermic or exothermic?

7. What is happening in your test tube?

D. Pour off the liquid into a second clean test tube.

8. What is this liquid composed of? What do you think would happen if you added more liver to this liquid? Why?

E. Add another 2 mL of hydrogen peroxide to the liver remaining in the first test

tube.

9. Can you observe any reaction? What do you think would happen if you poured off this liquid and added more hydrogen peroxide to the remain liver?

10. Are enzymes reusable?

Presence of CatalaseCatalase is present in many kinds of living tissues. You will now test for the presence of

catalase in tissues other than liver.

F. Place 2 mL of hydrogen peroxide in each of 3 clean test tubs. To the first tube,

add a small piece of carrot. To the second tube, add a small piece of potato. To

the third tube, add a piece of ham.

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As you add each test substance, record the reaction rate (0-5) for each tube

in Chart I of your data.

11.Which tissues contained catalase?

Part II: Effect of Temperature on Catalase Activity

G. Put a piece of liver into the bottom of a clean test tube and cover it with a small

amount of distilled water. Place this test tub in a boiling water bath for 5 minutes.

12.What will boiling do to an enzyme?

H. Remove the test tube from the hot water bath, allow it to air cool, and then pour

out the water. Add 2 mL of hydrogen peroxide. CAUTIION: Use a test – tube

holder when handling the hot test tubes.

13.What is happening in the test tube? Explain your results and record the reaction rate (0-5) in Chart II of your data table.

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I. YOU NEED 6 TEST TUBES FOR THIS STEP: Put equal quantities of liver into 3

clean test tubes and 2 mL H2O2 into 3 other test tubes. Put one test tube of liver

and one of H2O2 into each of the following water baths.

Ice bath (about 00C)

Room Temperature water bath (about 220C);

Warm water bath (about 270C)

J. After 3 minutes, pour each tube of H2O2 into the corresponding tube of liver and

observe the reaction.

14.Record the reaction rates (0-5) in Chart II of your data table.

15.Make a graph of the estimated reaction rate as a function of temperature.

Temperature should be your x-axis and the variables should be your y-

axis. You should have 4 points. 00C (ice water); room temperature (about

220C); warm water bath (about 270C) and 1000C (boiling).

16.What is the “optimum” temperature for catalase? (This is the temperature

at which the reaction proceeds fastest.)

17.Why did the reaction proceed slowly at 00C?

18.Why did the reaction not proceed at all at 1000C?

Post lab Analysis

19.Make an inference about what happens to the heat when the reaction

described in Step C occurs in living cells?

20.Did you find catalase to be present in all kinds of tissue tested today?

Explain why or why not.

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Name: _________________________ Block ________Score ______/20

Catalase Lab

Questions1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

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11.

12.

13.

14. Enter your data on Chart II.

15. Make a graph below your data tables.

16.

17.

18.

19.

20.

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Data Tables:

Chart I

Sample Rate of Enzyme Activity (0-5)Liver

Potato

Carrot

Ham

Chart II

Sample Rate of Enzyme Activity (0-5)

Ice bath (0 0 C)

Room Temperature water bath (220C)

Warm water bath (270C)

Boiling (1000C)

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Data Graph:Title _________________________________________

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Test Review

Complete 1 – 10 on page 57 of your textbook (Chapter 2 Assessment)1. 6.

2. 7.

3. 8.

4. 9.

5. 10.

Label the following diagram:

1.

2.

3.

8

OOxygen

15.999

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Label the maximum number of electrons that can be held at each level:

When atoms combine they either share electrons or transfer electrons. These two types of bonding are called:

sharing electrons

transfer of electrons

How does the left side elements different from the right-side elements on the Periodic Table?

How do the molecules change as you move down the columns?

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Match the term with the definition_ atom a. A group of atoms held together

by covalent bonds

_ ion b. Smallest particle of an element retains its chemical properties

_ electron c. Negatively charged particle moving \ around the nucleus

_ element d. Atoms that gain or lose electrons in chemical reactions

_ molecule e. A pure substance composed of only one type of atom

_ chemical bond a. Composed of molecules joined together in one large one

_ covalent bond b. Chemical bond in which atoms share electrons

_ ionic bond c. Molecules with carbon-carbon Bonds

_ macromolecule d. Force of attraction between oppositely charged ions

_ organic compound e. Force holding two atoms together; from a chemical reaction

Give the definition or an example of each

Mixture:

Solution:

Suspension:

How is a solution different from a suspension?

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Draw and label a water molecule:

Why is water considered polar if Oxygen and Hydrogen are sharing the electrons?

Match the property of water with the example

A) adhesionB) capillary actionC) cohesion D) surface tensionE) polarityF) Hydrogen bond

1 . A meniscus forms in a graduated cylinder.

2. Ionic compounds dissolve easily in water.

3. Xylem pulls water upward in a plant.

4. Heavy objects, which would normally sink, can sometimes remain on top of water.

5. Water has the ability to stick to itself.

What determines the pH of a solution?

Determine if it is an acid or a base

pH 1.4 __________ pH 7.8 __________

pH 4.2 ________pH 9.7 __________

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An unknown substance is added to a solution and the pH increases. The unknown substance is:

A. acidic

B. basic

C. solvent

D. sweet

Match the number bonds each element can make.

______1. Hydrogen A. 3

______2. Oxygen B. 4

______3. Nitrogen C. 2

______4. Carbon D. 1

Organic Compound List MoleculesC H N O P S

Quick Structure

Example Function

Carbohydrate

Protein

Lipid

Nucleic Acid

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What organic compound is an enzyme?

What effect do enzymes have on chemical reactions as they take place?

______________________________________________________________________

____________________________________________________________________

How does temperature and pH affect the rate of enzyme activity? Why?______________________________________________________________________

______________________________________________________________________

______________________________________________________________________

__________________________________________________________________

Draw and label the parts of the enzyme substrate complex: