Cette leçon contient 19 diapositives, avec diapositives de texte.
La durée de la leçon est: 80 min
Éléments de cette leçon
Slide 1 - Diapositive
Chemistry
One more time......
Slide 2 - Diapositive
Today you will learn
What are Reactants/Products ?
What are Endo/Exo-thermic reactions?
What does a reaction depend on to occur?
What is Lavoisier's Law of mass conservation
Slide 3 - Diapositive
How are we going to achieve this?
Theory --> Questions on erasing boards
Slide 4 - Diapositive
First question
What is a reaction?
a chemical process in which substances are changed into different substances, or one substance changes into others substances.
Slide 5 - Diapositive
First question
What is a reaction?
Slide 6 - Diapositive
So write on your board
Are these examples of a chemical reaction? Write Yes or No
1. Combustion of methane gas
2. Breathing in animals
3. Melting of water
Slide 7 - Diapositive
So write on your board
Are these examples of a chemical reaction? Write Yes or No
1. Combustion of methane gas
2. Breathing in animals
3. Melting of water
YES , YES, NO
Slide 8 - Diapositive
What are Reactants/Products of chemical reactions?
Slide 9 - Diapositive
What are Reactants/Products of chemical reactions?
Reactants: The substances that react to form a product
Product: The substance that is made/formed in a reaction
Slide 10 - Diapositive
Question 2:
Classify the substances in this reaction as Products and/or Reactants:
Methane gas is one of the most used substances in our lives to generate heat. It reacts with oxygen to generate heat. After Methane and oxygen react, water and carbondioxide are formed.
Slide 11 - Diapositive
R: methane, oxygen
P: water, carbondioxide
Slide 12 - Diapositive
Methane combustion generates heat?
Atoms in molecules are broken apart and rearranged.
Atoms never disappear/get used up
Depending on the reaction it sometimes requires heat/energy
Sometimes reactions generate heat
Slide 13 - Diapositive
Lavoisier's law of mass conservation
The mass of the reactants, is equal to the mass of the products because mass is never added/depleted in a reaction
Slide 14 - Diapositive
However, Energy/Heat does change after a reaction
Slide 15 - Diapositive
R1: The erlenmeyer becomes freezing cold after the reaction.
It took the heat from the surrounding area to make this reaction possible. It is
Slide 16 - Diapositive
R2: The erlenmeyer becomes very hot after the reaction.
La durée de la leçon est: 80 min
