Backwards Planning Lessons

3. Common observations of a chemical reaction are described in the introduction section. For each observation, name a common or everyday occurrence that must involve a chemical reaction?

Procedure: In this experiment, various chemicals were mixed together, to determine a reaction. Using two drops from chemical 1 and two drops of chemical two, unless otherwise stated, then recording the type of physical reaction or color changes that occurred.

reaction has taken place, for example a gad is given off or a solid is

to the unknown solution in order to completely precipitate the cations in part A. 2 A compound

1 litmus paper, red - in bag 2"x 3", Copper (II) Carbonate in Vial, 1/2 Full

A chemical reaction is when substances (reactants) change into other substances (products). The five general types of chemical reactions are synthesis (also known as direct combination), decomposition, single replacement (also known as single displacement), double replacement (also known as double displacement), and combustion. In this lab, the five general types of chemical reactions were conducted and observations were taken before, during, and after the reaction. Then the reactants and observations were used to determine the products to form a balanced chemical equation. The purpose of this lab was to learn and answer the question: How can observations be used to determine the identity of substances produced in a chemical reaction?

Heavy precipitate emerged immediately and solution turned white in color; solution then became opaque and turned light, bright blue in color.

Then in the last test tube fill it up with 5ml of sodium sulphate. Then after that carefully pour the sodium carbonate solution into the test tube labelled copper chloride solution examining the result and recording appropriately.

To discuss different types of chemical bonding in different substances (precursor to the next lesson topic)

Many signs show that a chemical reaction has occurred. Some ways we know there is a chemical reaction are the formation of gas, formation of precipitate, change in temperature, and,or change in color. In part one of the experiment, we know there was a chemical change because of the formation of the white precipitate. We poured the ammonia and water in the flask with alum and water, forming a white, cloudy substance in between the two liquids. The white, cloudy substance between the two is liquids is also known as aluminum hydroxide. The second part of the experiment was very similar to the first, but in the second part we mixed epon salt, water, and ammonia. The precipitate formed from mixing the epson salt, water, and ammonia was called magnesium hydroxide.

The purpose of this experiment is to distinguish the relationships between reactants and products, in addition to expanding on concepts such as single displacement reactions, mole ratio values, moles to mass, theoretical yields, limiting reactants, excess, stoichiometric relationships and percentage errors.

A few more important terms to keep in mind when doing a lab with chemical and physical changes are

A chemical reaction is a process in which elements or compounds react with one another to create new or different substances. There are two parts to a reaction. Those two parts are the products and the reactants. The reactants are the chemicals or chemical compounds that are going through the reaction itself. The products are chemical elements or chemical compounds that are produced as a result of the reactant or reactants reacting. There are four key indications that there’s a chemical reaction is taking place. Those four signs include a change in color and/or odor, formation of a precipitate or a gas, the release or absorption of energy (light, heat, electricity), and if the reaction is irreversible. Along with this information, there are ways to predict the products of a reaction.

Keeler J, Wothers P. Why chemical reactions happen. First edition. United States. Oxford University press Inc.

For this activity, students will be able to learn how water is a solvent by dissolving different substances, such as liquids and solids, into water. For this activity on solids and liquids will only be used, but gases can be dissolved in water, too. Some of the substances being used are: food color dyed water, oil, salt, sugar, flour, and coffee. In order to do this activity, the class will be split up into groups of four and will work together on this hands-on activity. It should take about fifteen minutes, but it could be shortened or lengthened. During the activity, the students will be filling out a worksheet that will show what substance(s) worked and did not work. There will also be follow-up questions to answer about the background information. By the end of the activity, the students will be educated on how and why water is the