1 / 20

3/15/12 - Bellringer

3/15/12 - Bellringer. What kind of reactions can you think of? (Think outside the box!) Turn in 4 bellringers from this week when finished. Objectives. 1. Identify the reactants and products in a chemical reaction.

manchu
Download Presentation

3/15/12 - Bellringer

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. 3/15/12 - Bellringer • What kind of reactions can you think of? (Think outside the box!) • Turn in 4 bellringers from this week when finished.

  2. Objectives • 1. Identify the reactants and products in a chemical reaction. • 2. Determine how a chemical reaction satisfies the law of the conservation of matter. • 3. Determine how chemists express chemical changes using equations

  3. Chapter 23 – Chemical Reactions 23.1 – Chemical Changes

  4. Chemical Reactions • Chemical reaction – a change in which one or more substances are converted to new substances • Reactants – the substances that react • Products – the new substances produced

  5. Different Reactions • Chemical reactions – use the ELECTRONS to form new substances • Nuclear reactions - use the NUCLEUS to form new substances • What does a chemical reaction look like?

  6. Chemistry Kitchen

  7. Chemistry Kitchen REACTANTS PRODUCTS

  8. Think about it… • If you burned a piece of paper, you end up with a pile of ashes. • Once burned, is there… • More mass? • Same mass? • Less mass? • Why?

  9. Conservation of Mass • Conservation of Mass - a Law that states in a chemical reaction, matter is not created or destroyed • Antoine Lavoisier experimented with mercury (II) oxide and heat • He found mass of products (liquid mercury and oxygen gas) equaled mass of reactants

  10. 3/19/12 - Bellringer • Boiling or freezing water is NOT a chemical reaction. Why? • Turn in 4 bellringers from lastweek if absent Thursday.

  11. Chemical Equation • Uses chemical formulas and symbols to describe a chemical reaction and the product(s) it produces • Chemical formula expresses the relationship between elements in the compound and molecules they make up

  12. Coefficients • Numbers which represent the number of units of each substance in a reaction • Knowing coefficients of chemical reactions allows chemists to use the correct amount of reactants to predict the amount of products (law of conservation applies)

  13. Example

  14. Subscripts and Symbols • Numbers which represent the number of atoms in a molecule of a particular element • Symbols used to show state of reactants • (s) solids • (aq) aqueous • (l) liquid • (g) gas

  15. Volcano with a Twist • Reactants? • Products?

  16. Equation: • NaHCO3 + CH3COOH => CH3COO-Na+ + H2O + CO2 • States? • Conservation?

  17. Notes Supplement • Chemical equations will look similar to… #AB(state) + # CD(state) → #AC(state) + #BD(state) Reactants (left) → Products (right) Arrow means “yields”

  18. Practice • SnO2(s) + 2 H2(g) → Sn(s) + 2 H2O(g) • CH4(g) + 2 O2(g) → CO2(g) + 2 H2O(g)

  19. In class assignment / homework: • Section 1 Reinforcement • Balancing Chemical Equations PART A AND B ONLY

  20. Closure Question • SnO2(s) + 2 H2(g) → Sn(s) + 2 H2O(g) • What are the reactants? • What are the products? • How is matter conserved / equalled out? • What changed? (Compounds and States)

More Related