Chem-speak (introduction to chemical equations)

Students will understand what constitutes a chemical reaction and how chemical equations represent chemical reactions by means of discussion and demonstrations.

A lesson plan for grades 9–12 Science

By Brenda Rock

Learn more

• Balancing Chemical Equations a tutorial on how to balance equations

Related pages

• Discovery Place and the Charlotte Nature Museum: Discovery Place offers hands-on activities in all areas of science for students at both the Discovery Halls and Charlotte Nature Museum.
• ZIPPLY delicious ice cream: Students explore states of matter when they change a liquid to a solid. Working in pairs, students make ice cream in a zip-lock bag. Science and technology are integrated with the use of graphic organizing software, word processing, digital photography and digital video.
• Making “Oobleck”: The students will discuss what they think will happen when mixing specific ingredients to create an unknown substance labeled “Oobleck.” Next, the students will work together in small groups of four or five to create this substance. Finally, the students will individually illustrate and write one to three sentences describing the results.

Related topics

• Learn more about chemistry and science.

Legal

Learning outcomes

Students will identify chemical changes and write balanced chemical equations.

Teacher planning

Time required for lesson

80 minutes

Materials/resources

• graphing calculator
• graphical analysis program by Vernier
• CBL / temperature probe by Texas Instruments
• molecular model kit
• 250 milliliter beakers
• balance
• graduated cylinder
• acetic acid
• ammonium chloride
• barium hydroxide octahydrate
• sodium bicarbonate
• sucrose
• concentrated sulfuric acid
• barium chloride
• dilute sulfuric acid

Technology resources

• CBL System by Texas Instruments
• graphing calculator
• graphical analysis program by Vernier

Pre-activities

Students should be familiar with the CBL and graphing calculators, and be able to write chemical formulas.

Activities

1. Key terms on overhead: reactant, product, coefficient, endothermic, exothermic, precipitate.
2. Instructor will demonstrate:
   • acetic acid (vinegar) reacting with sodium bicarbonate (baking soda)
   • sucrose reacting with sulfuric acid
   • ammonium chloride reacting with barium hydroxide oxyhydrate
   • barium chloride reacting with sulfuric acid
3. Use CBL temperature probe and graphing calculator to record and chart temperature change in reaction between ammonium chloride and barium hydroxide oxyhydrate.
4. After each reaction, students identify any indicators of a chemical reaction—color change, energy change, odor change and evolution of gas.
5. Instructor writes word equations for each of the four demonstrations and then translates into “chem speak” (i.e. writes chemical equations).
6. Demonstration with molecular model kit of molecular structure of ethyne, oxygen, carbon dioxide, and water.
7. Write word equation for reaction of ethyne burning in oxygen to produce carbon dioxide and water. Have students translate into “chem-speak.”
8. Have students check to see if the Law of Conservation of Mass has been observed.
9. Ask students to offer solutions for solving this problem.
10. Instructor leads students through balancing equation using coefficients.
11. Students use molecular model kit to rearrange the atoms to form CO₂ and 2 H₂O.
12. Worksheet with eight equations to be balanced.

Assessment

• feedback during discussions
• correct completion of equations worksheet

Supplemental information

Attachments:

• chemical equations worksheet