Chemistry 8 Lesson 25: Oxidation – Compound reactions – Uses of oxygen
1. Summary of theory
– The reaction of oxygen with a substance.
1.2. Synthetic reaction
A chemical reaction is a chemical reaction in which a new substance is formed from two or more starting substances.
The above reactions take place at high temperature.
1.3. Applications of Oxygen
Oxygen is needed for:
– Respiration of humans and animals.
– The burning of fuel in life and production.
2. Illustrated exercise
Write a mathematical equation, classify chemical reactions
Lesson 1. Write the equations for the following reactions:
a. Cu + O2 → ?
b. S + O2 → ?
c. Fe + O2 → ?
d. CO + O2 → ?
e. OLD2H4 + O2 →?
a. Cu + O2 → 2CuO
b. S + O2 → SO2
c. 2Fe + 2O2 → Fe3O4
d. CO + O2 → CO2
e. OLD2H4 + 3O2 → 2CO2 + 2 HOUSES2O
Lesson 2. Write the equations for the following chemical reactions:
a. Burning aluminum in oxygen gas.
b. Quicklime CaO with carbon dioxide gas creates limestone CaCO3.
a. 4Al + 3O2 → Al2O3
b. CaO + CO2 → CaCO3
3.1. Essay exercises
Question 1: Write a mathematical equation representing the chemical reaction of sulfur with the following metals. (Know in compound S has valence II).
Verse 2: Balance the following chemical equations, which reaction belongs to a chemical reaction?
a. CuO + HCl → CuCl2 + H2O
b. KMnO4 → K2MnO4 + MnO2 + O2
c. P2O5 + H2O → H3PO4
d. CaCO3 + CO2 + H2O → Ca(HCO3)2
Question 3: For the reaction CaO + H2O → Ca(OH)2. Calculate the number of moles of calcium hydroxide given the mass of CaO is 5.6 g?
3.2. Multiple choice exercises
Question 1: Which reaction is a chemical reaction?
A. Cu + HIM2SO4 → CuSO4 + FRIENDS2
B. CaO + H2O → Ca(OH)2
C. CaCO3 → CaO + CO2
D. Fe + 2HCl →FeCl2 + FRIENDS2
Verse 2: The most important fields are only oxygen gas
B. Fuel Combustion
C. Used in chemical reactions
D. Both A&B
Question 3: Choose the wrong answer
A. The reaction of oxygen with a substance is oxidation
B. Oxygen-rich air furnace
C. Cu + HO2SO4 → CuSO4 + FRIENDS2 is a chemical reaction
D. Oxygen-acetylene torch is one of the uses of oxygen
Verse 4: Choose the correct answer
A. In the 19th century, oxygen was often mixed with nitrous oxide as a pain reliever
B. Oxygen is used as a reducing agent
C. A chemical reaction is a substance that, after heating, forms 2 substances
D. All 3 answers
Question 5: Why do patients need a breathing tube when breathing is unstable?
A. Provide oxygen
B. Raised body temperature
C. Blood circulation
D. Pain relief
After the lesson to know:
- What are the uses of oxygen?
- How is the oxidation?
- What is a chemical reaction?