1 / 23

Chemical formulae and chemical equations

Chemical formulae and chemical equations. Chemical equations. Review of Prior knowledge. Can you write the chemical formula of the following substances? Magnesium chloride Carbon dioxide Methane Aluminium Sulfate. Welcome to the 101th CVSS chemistry awards.

krista
Télécharger la présentation

Chemical formulae and chemical equations

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. Chemical formulae and chemical equations Chemical equations

  2. Review of Prior knowledge Can you write the chemical formula of the following substances? • Magnesium chloride • Carbon dioxide • Methane • AluminiumSulfate

  3. Welcome to the 101th CVSS chemistry awards. • To find out if you have been nominated for most outstanding chemistry award please check under your desk.

  4. Objectives for the day… • Construct chemical equations, with state symbols, including ionic equations. • Interpret chemical equations with state symbols. • Construct ionic chemical equations.

  5. Objective 1: Constructing chemical equations, with state symbols, including ionic equations • An equation can be written in words – a word equation. sodium + chlorine  sodium chloride • An equation can also be written with symbols and formulae instead of words – a chemical equation. 2Na + Cl2 2NaCl

  6. In a Chemical Reaction: A process in which at least one new substance is produced as a result of chemical change • Reactants used. • Products formed. Reactants Products

  7. Analogy Ingredients: 12 oz of dough 4 ozmushroom 12 slices pepperoni 8 oz cheese 5 oz tomato sauce These ingredients are used to make a pizza. How would you write the recipe in word equation for putting together a pizza? 12 oz dough + 4 oz mushroom + 12 slices pepperoni + 8 oz cheese + 5 oz tomato sauce  1 pizza

  8. Constructing Chemical Equations What Chemical Equations Show • The reactants used. • The products formed. • The states of the reactants and products. • The arrow means ‘react to form’ and reaction proceeds from left to right). Reactants Products Eg: 2Mg (s) + O2(g) 2MgO (s) State symbols

  9. hydrogen + oxygen water 2H2(g) + O2(g) 2H2O(l) Constructing Chemical Equations The Reaction Between Hydrogen and Oxygen • Word equation: • Chemical equation: State symbol

  10. Constructing Chemical Equations Balancing Equations • All chemical equations (with state symbols) must be balanced. • A balanced equation: • shows the formulae of all the reactants and all the products in a reaction. • has the same number of atoms of each element on both sides of the equation.

  11. Law of Conservation

  12. Balancing equation

  13. Balancing equation 13

  14. Balancing equation C atom = 1 H atoms = 4 O atoms = 2 C atom = 1 H atoms = 2 O atoms = 2 + 1 = 3 Not Balanced 14

  15. Balancing equation 2 2 C atom = 1 H atoms = 4 O atoms = 4 C atom = 1 H atoms = 4 O atoms = 4 Balanced 15

  16. Balancing equation 16

  17. Learning Check for Balancing Equation Al + Cl2  AlCl3 17

  18. Balancing equation Al atom = 1 Cl atoms = 2 Al atom = 1 Cl atoms = 3 Not Balanced 18

  19. Balancing equation 2 3 2 Al atom = 2 Cl atoms = 6 Al atom = 2 Cl atoms = 6 Balanced

  20. Balancing equation

  21. Learning check for Balancing equation Write the balanced chemical equation with state symbol. Iron + oxygen gas  Iron(III) oxide 4Fe (s) + 3O2 (g)  2Fe2O3 (s) Sodium + bromine  sodium bromide 2Na (s) + Br2 (l)  2NaBr (s)

  22. Learning Objective 2: Interpret chemical equations with state symbols 2Na + Cl2 2NaCl • Two atoms of Na react with one molecule of Cl2to produce 2 unit of NaCl.

  23. What did we learn this lesson… • What is a word equation. • What is a chemical equation. • What is a reaction (reactants and products). • What is law of conservation. • How to write a balanced equation with state symbols. • How to deduce a chemical equation.

More Related