John Dalton

1. John Dalton ReViEw • The main reason in which substances change in a chemical reaction was propose by John Dalton in his atomic theory. This explanation still holds true today. In a chemical reaction atoms are joined together and changed. As reactants are converted to products , bonds that hold atoms together are broken and new bonds are formed. The atoms themselves are neither created or destroyed.

2. Chemical Equation In a chemical equation, an arrow separates the formulas of the reactants (on the left) from the formulas of the products (on the right). Fe+O2→Fe2O3 Reactants→ Products

3. Symbols are used to now what type of compounds you’re using, and the relationship between the formulas.

4. Definitions • Catalyst: a substance that speeds up a reaction without being used up. • Skeleton Equation: A chemical equation that does not indicate the relative amount of the reactants and products.

5. 1. Fe(s)+O2(g) Fe2O3(s) H2O 2. Fe(s)+O2(g) Fe2O3(s) What is the difference between the two above equations? 1.) In the first equation there is a chicken. 2.) The same formulas in the equations have different states of an element. 3.) There is a catalyst in the 2nd equation.

6. How we use it in everyday life

7. Different ways of writing chemical equations: • You can use the actual formulas: • H2CO3(aq)  →   H2O(l) + CO2(g) • Or you can write out your equation with words: • Carbonic acid in water decomposes when formed. It decomposes to liquid water and gaseous carbon monoxide.

8. homework 1). Explain why John Dalton is important? 2). Tin dioxide and dihydride makes Tin and water. Write the skeleton equation. 3).Carbon tetrahydride and dioxide makes carbon dioxide and water. Write the skeleton equation