ROUTERA

Metals and Non-metals

Class 10th Science Chapter Case Study

Case Study 1: The Properties of Metals

Case Description:
Metals are known for their distinct physical and chemical properties. They are generally solid at room temperature (except for mercury), have high melting and boiling points, and are good conductors of heat and electricity. These properties make metals suitable for a wide range of applications, including construction, electrical wiring, and manufacturing of tools. Understanding these properties helps in selecting the right metals for specific purposes.

MCQs:

  1. Which of the following is a characteristic property of metals?

    • A) Brittle
    • B) Dull appearance
    • C) High melting point
    • D) Poor conductors of heat

  2. Which metal is liquid at room temperature?

    • A) Gold
    • B) Aluminum
    • C) Mercury
    • D) Iron

  3. Metals are generally:

    • A) Insulators of electricity
    • B) Good conductors of heat
    • C) Gases at room temperature
    • D) Soft and malleable only

  4. Which of the following metals is used for making electrical wires due to its excellent conductivity?

    • A) Copper
    • B) Lead
    • C) Zinc
    • D) Tin

Case Study 2: The Reactivity of Metals

Case Description:
Metals vary in their reactivity with acids and water. Some metals, like potassium and sodium, react vigorously with water, while others, like gold and platinum, are quite unreactive. Understanding the reactivity series helps in predicting how different metals will behave in chemical reactions. For instance, a more reactive metal can displace a less reactive metal from its salt solution.

MCQs:

  1. Which of the following metals reacts vigorously with water?

    • A) Gold
    • B) Iron
    • C) Sodium
    • D) Copper

  2. In the reactivity series, which metal is least reactive?

    • A) Sodium
    • B) Zinc
    • C) Gold
    • D) Iron

  3. What happens when zinc reacts with hydrochloric acid?

    • A) No reaction occurs
    • B) Produces hydrogen gas
    • C) Forms a metal hydroxide
    • D) Produces oxygen gas

  4. Which of the following statements is true about displacement reactions involving metals?

    • A) A more reactive metal can displace a less reactive metal.
    • B) A less reactive metal can displace a more reactive metal.
    • C) Only non-metals can displace metals.
    • D) Metals do not participate in displacement reactions.

Case Study 3: The Formation of Ionic Compounds

Case Description:
Metals typically lose electrons to form positive ions (cations), while non-metals gain electrons to form negative ions (anions). When metals and non-metals react, they form ionic compounds through the transfer of electrons. For example, sodium reacts with chlorine to form sodium chloride (table salt). Understanding how ionic compounds are formed helps in grasping the principles of chemical bonding.

MCQs:

  1. What type of bond is formed between sodium and chlorine?

    • A) Covalent bond
    • B) Metallic bond
    • C) Ionic bond
    • D) Hydrogen bond

  2. What happens to sodium when it reacts with chlorine?

    • A) Sodium gains electrons.
    • B) Sodium loses electrons.
    • C) Sodium forms a covalent bond with chlorine.
    • D) Sodium remains neutral.

  3. Which of the following statements is true about ionic compounds?

    • A) They are always liquid at room temperature.
    • B) They conduct electricity in solid state.
    • C) They have high melting and boiling points.
    • D) They are formed between two metals.

  4. Which ion does chlorine form when it gains an electron?

    • A) Cl
    • B) Cl⁻
    • C) Cl²⁻
    • D) Cl⁺

Case Study 4: Non-Metals in Everyday Life

Case Description:
Non-metals have a variety of applications in daily life, including in the formation of compounds and as essential nutrients. For instance, nitrogen is a major component of the atmosphere and is crucial for plant growth. Phosphorus is used in fertilizers, while sulfur is used in the production of sulfuric acid, one of the most widely used industrial chemicals. Understanding the role of non-metals helps us appreciate their significance in various processes.

MCQs:

  1. Which non-metal is essential for plant growth and is a key component of fertilizers?

    • A) Nitrogen
    • B) Argon
    • C) Helium
    • D) Chlorine

  2. What is sulfur commonly used for in industries?

    • A) Electrical wiring
    • B) Production of sulfuric acid
    • C) Making jewelry
    • D) Construction materials

  3. Which of the following is a property of non-metals?

    • A) High melting and boiling points
    • B) Good conductors of electricity
    • C) Dull appearance
    • D) Malleable and ductile

  4. What gas is produced when non-metals react with oxygen?

    • A) Metal oxides
    • B) Non-metal oxides
    • C) Ozone
    • D) Hydrogen gas

Case Study 5: The Importance of Alloys

Case Description:
Alloys are mixtures of two or more elements, where at least one of the components is a metal. They are designed to enhance certain properties, such as strength, corrosion resistance, or malleability. For example, steel is an alloy of iron and carbon, which is stronger than iron alone. Understanding the properties and uses of alloys is essential in fields like construction, manufacturing, and technology.

MCQs:

  1. What is steel primarily composed of?

    • A) Iron and nickel
    • B) Iron and carbon
    • C) Copper and zinc
    • D) Aluminum and tin

  2. Which of the following is a property of alloys?

    • A) They are always less dense than pure metals.
    • B) They have properties different from their component elements.
    • C) They cannot conduct electricity.
    • D) They are always malleable.

  3. Which of the following alloys is used in making aircraft due to its light weight and strength?

    • A) Bronze
    • B) Steel
    • C) Aluminum alloy
    • D) Copper alloy

  4. Which is NOT a common use of alloys?

    • A) Jewelry making
    • B) Electrical wiring
    • C) Fuel production
    • D) Construction materials