Chemical reactions-6.2

Identify the parts of a chemical reaction

Chemical v. Physical

• Is boiling water an example of a chemical reaction?

• Demonstrate chemical v. Physical change

• 3 pieces of paper: Identify the change?

a) Burned corners

b) Cut corners

c) Hole in the middle

3-column Notes

• Chemical reaction, reactant, product, activation energy, catalyst, enzyme, substrate, active site

• term→ prediction → definition → example

Chemical reactions

• WHAT IS THE RELATIONSHIP BETWEEN A CHEMICAL BOND AND A CHEMICAL REACTIONS?

Chemical reactions allow living things to grow, develop, and adapt

• Reactant → Products: (Parts of a reaction)

• C6H12O6 + O2 → CO2 + H2O

• glucose and oxygen reacts to form carbon dioxide and water

• Balanced equilibrium: use of coefficients number written in front of reactant/product

• conservation of mass—matter cannot be created nor destroyed

Explain why chemical equations must be balanced.

• C6H12O6 + O2 → CO2 + H2O

• C6H12O6 + 6O2 → 6CO2 + 6H2O

• Practice balancing equations:

• K + B2O3 → K2O + B

• 6K + B2O3 → 3K2O + 2B

Practice

• 1. HCl + NaOH → NaCl + H2O

• 2. CH4 + O2 → CO2 + H2O

• 3. N2 + H2 → NH3

• 4. Al + S8 → Al2S3

Answers

• 1. HCl + NaOH → NaCl + H2O

• 2. CH4 + 2O2 → CO2 + 2H2O

• 3. N2 + 3H2 → 2NH3

• 4. 16Al + 3S8 → 8Al2S3

Activation energy

• The minimum amount of energy needed for reactants to form products in a chemical reaction.

• Figure 6.15 and 6.16-skill practice-visual literacy- read text under Activation energy and enzymes.

Activation Energy

• Consider how fig.6.17 depicts key concepts. Draw graphs showing effect of a catalyst on the activation energy needed for a chemical reaction.

• What are enzymes?

• Why are enzymes important to living things?

• Name some biological processes that require enzymatic activity.

• What effect does an enzyme have on a chemical reaction?

Key and Lock

• How do enzymes maintain specificity?• Evaluate: formative assessment• Relate this concept to the analogy “key

and lock”.• List the factors that may alter the activity of

an enzyme.• Enzymes: describe the conditions inside

the cell that enable enzymes to be active.

Water and Solution 6.3

• The properties of water make it well suited to help maintain homeostasis in an organism.

• OBJECTIVE:

• Compare and contrast solutions and suspensions.

• Describe the difference between acids and bases

1st Objective

• Evaluate how the structure of water makes it a good solvent.

• Physical property: characteristic of matter, such as color or melting point, that can be observed or measured changing the composition of the substance.

3-Column Notes

• Polar molecule, hydrogen bond, mixture, solution, solvent, solute acid, base, pH, buffer.

• term→ prediction → definition → example

Water Properties

• Polar molecule-what does it mean to have polarity?

• Adhesion—able to stick to surfaces

• Cohesion-able to stick to itself

• High specific heat-moderates temperature

• Floats when it freezes-expands

• Versatile solvent

Morphological Word Analogy

• Homogeneous v. heterogeneous

• Predict the meaning of these terms

• Use the Internet to search for these terms and write down some of what you find.

• Brainstorm examples of each term

• Discuss the meaning of these terms

Acids and Bases

• Acids: on a pH scale 0—6, (7—neutral)

• Bases: on a pH scale 8—14

• Data Analysis Lab 6.1, pp. 164 complete.

• pH and buffers-balance solutions to maintain equilibrium= strong acid + strong base= a salt + water

The Building Blocks of Life

• Organic Chemistry- compounds containing C.H. O in a 1:2:1 ratio- see glucose

• Inorganic Chemistry-compounds not containing C, H, O in a 1:2:1 ratio like hydrogen carbons

• Four macromolecules are organic

• Carbohydrates, proteins, lipids, nucleic acids (DNA→RNA)

What does it mean to be organic?

• Objectives: describe the role of carbon in living organisms. Summarize the four major families of biological macromolecules. Compare the functions of each group of macromolecules.

• Terms: macromolecules, polymer, lipids, carbohydrates, proteins, amino acids,

Nucleotides.

Complete the table

• Chemical/ symbol: carbon/ C, hydrogen, oxygen, nitrogen, phosphorous, sulfur.

• Atomic Number: 6

• Atomic Mass: 12

• Bonds Formed: 4

Clarify Misconception

• If a vegetable farmer grows crops without the use of chemical fertilizers and pesticides, is the produce considered organic?

• Organic molecules:

• Organic foods

Differentiate

• Starch is a polysaccharide, dissolves easily in water, whereas cellulose does not. Both molecules consists of polymers of glucose molecules (sugar).

• What structural difference between starch and cellulose accounts for their difference in solubility?

Lipids

• Saturated fats:

• Unsaturated fats:

• Phospholipids:

• Steroids:

Anticipation Guide

• Before reading about Proteins: Predict T/F

• 1. proteins are organic molecules

• 2. proteins are made in cells

• 3. enzymes are proteins

• 4. amino acids are the building blocks of proteins

Clarify misconceptions

• What types of food other than meats are rich source of proteins?

• 20 different amino acids occurs in a triple code—a codon.

• Protein structurally in primary, secondary, tertiary, quaternary,

Nucleic acids DNA/ RNA

• Nucleotides—subunits

• DNA’s sugar-Deoxyribose

• RNA’s sugar---Ribose

• Nitrogenous base—purines and pyrimidine

Purines—Adenine and Guanine

Pyrimidine---Thymine and Cytosine

Bonds A—T and G—C

Formative assessment

• What is the relationship between macromolecules and polymers?

• What are the four categories of macromolecules?

• Study for chapter 6 test on Wednesday.