The first chapter of the 9th science book titled “Materials and their role in life” is one of the most important chapters of this book, and in order to gain sufficient mastery of its contents, you need to study more questions and answers from this chapter. section Tutorial content Setareh has prepared the text questions of the first chapter of the 9th science along with explanatory answers and textbook activities for you, which will help you prepare Be fully present at the exam session and get an excellent grade from this season.
1- Name the two main groups of materials?
Answer:
1) Pure materials
2) Mixed materials
2- Name two categories of pure substances?
Answer:
1) Element
2) Composition
3- In addition to dividing materials into pure and mixed, how many other groups can they be divided into?
Answer:
1) Materialnatural
2) Artificial
4- Name two categories of elements?
Answer:
1) Metal
2) non-metal
5- Define element and composition with example:
Answer:
Element: Substances made of one type of atom; For example: pure silver
Composition: It consists of two or more types of atoms; For example: air = oxygen + nitrogen
6- What is the first metal extracted from ore?
Answer: copper metal
7- Name the characteristics of copper element:
Answer:
1) Copper is a solid metal.
2) It has a shiny and red surface.
3) It is hard and malleable.
4) It is a conductor of electricity and heat.
5) It is the first metal extracted from ore.
6) Copper metal is obtained by melting its ore at high temperature and plays an important role in the country’s industry.
8- Name the uses of copper:
Answer:
1) Cooking food
2) Ability to be wired
3) Building wiring
4) High electrical conductivity
5) Corrosion resistance
9- What is the name of the first copper metal mine?
Answer: Sarcheshme copper mine
10- Write the written equation for the production of copper oxide?
Answer: Copper oxide, oxygen gas + copper metal
11- Write the written equation of iron oxide production?
Answer: Iron oxide, oxygen gas + iron metal
12- If you hold a piece of ……… on the flame of a lamp, it will burn quickly and produce a dazzling light.
Answer: Magnesium bar
13- Why is copper used instead of iron in making dishes?
Answer: Because the affinity of copper with oxygen is lower than that of iron.
14- Metals do not have the same reactivity. (give an example)
Answer:
Responsiveness slow with oxygen such as iron and copper metal.
Responsiveness sharp with oxygen such as magnesium.
without Reaction like gold.
15- Name a homogeneous gaseous mixture?
Answer: air
16– Name the most important constituents of air?
Answer: Nitrogen, oxygen, argon and carbon dioxide
17- Write the chemical formula of oxygen and ozone?
Answer:
Oxygen: Diatomic O2 is a pure substance of a non-metal element
Ozone: O3 is a triatomic pure substance of a non-metal element
18- What is the benefit of ozone gas?
Answer: It prevents the arrival of energetic and dangerous ultraviolet rays.
19- What is ozone and explain its role?
Answer: Ozone gas with formula 13 exists in the upper layers of the earth. Ozone gas prevents the energetic and dangerous ultraviolet rays from reaching the earth and acts as a protective layer.
20- What is the purpose of drawing atomic arrangement?
Answer:
1) The number of electrons in the last orbit of each atom
2) The position of the atom in the periodic table
21- State the use of phosphorus and carbon?
Answer: Nitrogen gas is used as a raw material for the production of ammonia, ammonia is also used in the preparation of chemical fertilizers and explosives.
22- What is the nitrogen cycle?
Answer: The continuous circulation of nitrogen between soil, water, air and living organisms is called nitrogen cycle.
23- State the use of nitrogen gas?
Answer: Carbon is used in making pencils and phosphorus is used in making matches.
24- Write the chemical formula of sulfuric acid?
Answer: H2SO4
25- Write the uses of sulfuric acid?
Answer: Chemical fertilizer – shoes – detergent – car paint – battery – paint
26- What elements are there in sulfuric acid?
Answer: Hydrogen – Sulfur – Oxygen
27- How many atoms is ytrogen in nature?
Answer: Diatomic
28- What is sodium?
Answer: Sodium is a solid metal that reacts strongly with water and oxygen and is therefore highly reactive.
29- Write the chemical equation of ammonia production?
Answer: Ammonia gas, hydrogen gas + nitrogen gas
30- Write some uses of chlorine and its compounds.
Answer:
1) Criminalization
2) Water disinfectant
3) Preparation of hydrochloric acid
4) Agriculture
31- Which of the following are semi-metals? (magnesium – silicon – platinum)
Answer: Silicon, semi-metal, is a title for the classification of chemical elements, which refers to elements whose properties are between metal and non-metal. Semi-metals are usually semi-conductors.
32- State two uses of ammonia gas?
Answer: Preparation of chemical fertilizers and explosives
33- Why do classifications make it easy to study elements?
Answer: Because the elements that are placed in the same class have relatively the same properties.
34- Define polymer with an example.
Answer:
Definition of polymer: A group of macromolecules that are made of thousands of smaller units called (monomers). These monomers can be identical, such as glucose in the structure of cellulose and starch, or not identical, such as 62 types of amino acids in the structure of proteins.
35- Name the types of polymers with examples:
Answer:
Natural polymer: Like protein, wool, silk, cotton, cellulose, glycogen, starch, hemoglobin, olive oil
Unnatural polymer (synthetic): such as Teflon plastic, PVC and…
36- Name examples of natural polymers.
Answer: Wool, silk and cotton.
37- What are the disadvantages of using plastics?
Answer:
1) Plastics do not decompose easily in the environment and remain in nature for long periods of time.
2) Burning them also releases toxic fumes into the air. That’s why they return them.
38- What are the main uses of synthetic polymers?
Answer:
1) Production of car parts
2) Use in building materials
3) Packaging of all kinds of products
4) Making bottles and personal items
39- What is the important role of iron, sodium and potassium elements in the body?
Hawab:
1) Iron is necessary for the production of hemoglobin in the blood.
2) Sodium and potassium are effective in the proper functioning of the heart.
3) Iodine plays a role in regulating the body’s metabolic activities.
4) Calcium is effective in the process of bone growth.
40- Explain the advantages and disadvantages of synthetic polymer with an example:
Answer:
Advantages of synthetic polymers: They do not suffer from corrosion, they are malleable, they are light, they are thermal and electrical insulation, they are cheap, they have relatively high strength, they have a long life.
Disadvantages of synthetic polymers: They don’t decompose easily in nature, they emit toxic fumes into the air when they burn, they don’t have the quality of natural fibers.
41- What is fluorine and what is its use?
Answer: Fluorine is one of the chemical elements added to toothpaste to prevent tooth decay. The atom of this element has 7 electrons in its last orbit and therefore has special properties.
42- What are the appearance characteristics and location of sulfur?
Answer: Sulfur is a yellow solid substance that is usually found in areas near the craters of dormant and semi-active volcanoes.
43- What is the reactivity of metals with oxygen?
Answer:
1) Iron reacts slowly with oxygen and produces iron rust.
2) Copper slowly combines with oxygen and produces copper oxide.
3) Magnesium burns quickly and produces a lot of light.
4) Gold does not combine with oxygen and is therefore known as a stable metal.
44- What metals are among the most widely used metals?
Answer: Copper, gold, aluminum and iron.
45- From what source is the raw material for the production of synthetic fibers obtained?
Answer: The raw material of synthetic fibers is obtained from the oil industry.
46- Name the role of elements in physical activities.
Answer:
1) Iron in the structure of blood hemoglobin
2) Sodium and potassium in cardiac activities
3) Iodine in regulating body activities (cell fuel)
4) Calcium in the growth of bones and teeth
47- ……. It is a natural polymer.
Answer: Cellulose
The answer to collecting information, page 2, chapter one, experimental sciences, ninth
Collect information about how different metals have been used since their discovery and report to the class by referring to reliable sources.
Answer:
Iron: Four thousand years BC, the Sumerians and Egyptians made small items such as bayonets and ornaments with the iron discovered from meteorites, iron smelting in the furnace was done from two to three thousand years BC.
Copper: The use of copper dates back to 10,000 BC. 5 thousand years before Christ, copper dishes were made in Iran, and 3 to 4 thousand years before Christ, they used copper to make items such as earrings and knives.
Gold: The oldest gold mine was discovered by the Sumerians in Mesopotamia in 4000 BC. In the second millennium BC, there were goldsmith workshops in Egypt, in the seventh and eighth centuries BC in ancient Greece, and in the first century BC in Armenia, the first gold coins became popular.
Test your answer, page 3, chapter 1, experimental sciences, 9th
Read the above text carefully once more and answer the following questions.
Source Link
