Quarter 1 Sect ion 1.3 Name:

Quest ion of the Day:

1. What is the difference between an ionic and covalent bond?

2. The atomic number of argon is 18 and it is in group VIIIA. Will argon tend to form bonds with other elements? Explain your answer.

Latin Root Word

Review of Old Informat ion: N/A

New Informat ion:

One of the most important characteristics in all living things is that they all use energy. Yesterday, we looked at the ability of different elements to form chemical bonds. When this occurs, these chemical reactions allow for energy to be exchanged and change forms. When biologists study the chemistry of living things, it is very important for them to understand the different types of energy and how the various types of energy impact living things. See page 35 in your textbook to assist with the material below: Notes:

Types of React ions 1. _______________ React ions

Reactants have ___________ free energy than the products

Involve a net __________ of energy 2. _______________ React ions

Reactants have _________ energy than the products

Involve a net __________ of energy

For each of the fo l lowing descr ipt ions, say whether the process is endothermic or exothermic and give a reason for your answer. 1. Evaporation: _______ 2. The combustion reaction in a car engine: _______ 3. Bomb explosions: _______ 4. Melting ice: _______ 5. Digestion of food: _______ 6. Condensation: _______ Chemica l React ions Chemical reactions need an initial ____________ of energy = THE _________________ ENERGY During this part of the reaction the molecules are said to be in a _______________ state. Reaction pathway: Draw and Label… How to make reactions go faster = add a CATALYST Enzymes can ________________ the rate of reactions without increasing the ________________. They do this by lowering the _______________ energy. They create a new reaction pathway “a short cut” What are ________________ Most enzymes are _____________ Act as Catalyst to ______________ a reaction

How do enzymes work? Enzymes work by _____________ bonds, which __________ the activation energy needed to break up the ____________ so new compounds can form (which we call products). In order for a substance to change its state from a solid to a liquid, would thermal energy need to be “added to” or “taken away” from the substance? __________________________________________ Most of the energy in your body is transferred from one form to another through series of many thousands of chemical reactions. Every chemical reaction has two types of substances. _______________ are typically shown on the left side of a chemical equation, while _______________ are shown on the right side (SEE EXAMPLE BELOW). 2H2 + O2 2H2O

reactant + reactant product

The energy needed to power your body comes from the different types of foods you eat. Your body is continuously undergoing a series of chemical reactions to break down, or metabolize, these foods. When this occurs, energy is released for your body to use. These reactions that involve a net release of energy are called _______________ reactions. Reactions that involve a net absorption of energy are called _______________ reactions.

For these exergonic and endergonic reaction to occur, energy almost always needs to be added to the reactants. This is typically called _________________ energy. Chemicals that can reduce the amount of activation energy needed for a reaction to occur are called _______________. Catalysts in living things are typically referred to as _______________.

Activity: Video Questions

1. Was the reaction performed an exergonic or endergonic reaction? How can you tell?

2. A ____________________ reduces the activation energy needed for a chemical reaction to occur.

3. What was the catalyst in this demonstration? __________________________________________

4. Was the reaction performed an exergonic or endergonic reaction? How can you tell?

5. A ____________________ reduces the activation energy needed for a chemical reaction to occur.

6. What was the catalyst in this demonstration? __________________________________________ CATECHOLASE: LAB Procedure: 1. Prepare catecholase by thoroughly blending potatoes (15 g/100 ml of water) in distilled water. Filter through cheese cloth. Put filtrate in dropper bottle. 2. Fill each of two test tubes 1/4 full (3 ml) of distilled water. 3. Add 10 drops of catechol to each tube. 4. Add 10 drops of potato extract to one tube, label C. 5. Add 10 drops of distilled water to the unlabelled test tube. Mix. 6. Note and record color of each tube at 1-minute intervals for 5–10 minutes.