Explore the properties, reactions, and practical uses of metals and non-metals. This guide covers key concepts such as malleability, ductility, and conductivity, alongside the differences between metals and non-metals. It includes examples of various elements, their interactions with acids and bases, and the types of oxides they form. Topics like displacement reactions, the reactivity series, and the reasons behind material selection for machinery, utensils, and construction are also explained. With clear and structured answers, this resource is perfect for students, educators, and anyone interested in understanding the role of chemistry in daily life.
1) What are some examples of metals and non-metals?
Answer: Metals: Iron, Aluminum, Copper. Non-metals: Coal, Sulfur.
2) How can metals be distinguished from non-metals?
Answer: Based on their physical and chemical properties.
3) What are the two physical properties of metals and non-metals?
Answer: Lustre, hardness, Malleability, and ductility.
4) What happens when you beat an iron nail with a hammer?
Answer: It flattens.
5) What happens when you beat a coal piece with a hammer?
Answer: It breaks into pieces.
6) Which materials were malleable (flattened) and which were not(coal piece, pencil lead, Iron nail, Aluminum wire)?
Answer: Malleable: iron nail, Aluminum wire; Not malleable: coal piece, pencil lead.
7) What is the difference between malleability and ductility?
Answer: Malleability is the ability to be beaten into thin sheets, while flexibility is the ability to be drawn into wires.
8) Name some malleable materials.
Answer: Iron, Aluminum, Copper.
9) Can coal and pencil lead be considered metals based on their properties?
Answer: No, because they are not malleable or ductile.
10) What term describes materials that allow electricity to pass through them?
Answer: Good conductors.
11) What term describes materials that do not allow electricity to pass through them?
Answer: Poor conductors.
12) Name some materials that are good conductors of electricity.
Answer: Iron rod/nail, copper wire.
13) Name some materials which are poor conductors of electricity.
Answer: Sulfur, coal piece.
14) Does the sound produced when dropping an iron sheet, a metal coin, and a piece of coal on the floor differ?
Answer: Yes, there is a difference in the sound produced. The exact nature of the difference would depend on the specific materials and the experiment conditions.
15) What are the characteristics of metals that distinguish them from non-metals?
Answer: Metals are generally hard, lustrous, malleable, ductile, sonorous, and good conductors of heat and electricity. Non-metals are often soft, dull, and poor conductors.
16) What are some examples of metals and non-metals?
Answer: Metals: Iron, Copper, Aluminum, Calcium, magnesium. Non-metals: sulfur, carbon, oxygen, phosphorus.
17) Are there any exceptions to the general properties of metals?
Answer: Yes, sodium and potassium are soft metals, and mercury is a liquid metal at room temperature.
18) What term describes materials that produce a ringing sound when struck?
Answer: Sonorous.
19) What happens when iron, oxygen, and water react?
Answer: Rust is formed.
20) What is the nature of the solution formed when rust is dissolved in water?
Answer: Acidic.
21) What are the products of the reaction between magnesium and oxygen?
Answer: Magnesium oxide (MgO).
22) Why do metals have a shiny appearance?
Answer: Due to their ability to reflect light.
23) What is the significance of the malleability and ductility of metals?
Answer: These properties make metals useful for various applications like making sheets, wires, and utensils.
24) Why are metals good conductors of heat and electricity?
Answer: Due to the presence of free electrons that can move easily through the metal lattice.
25) What happens when copper is exposed to moist air for a long time?
Answer: It acquires a dull green coating.
26) What is the green material formed on the surface of copper vessels?
Answer: A mixture of copper hydroxide (Cu(OH)₂) and copper carbonate (CuCO₃).
27) What is the chemical reaction involved in the formation of this green material?
Answer: 2Cu + H₂O + CO₂ + O₂ → Cu(OH)₂ + CuCO₃.
28) What happens when sulphur is heated in a deflagrating spoon?
Answer: It starts burning.
30) What should be done to collect the gas produced when sulfur burns?
Answer: Introduce the burning spoon into a gas jar/glass tumbler and cover it with a lid.
31) How can the nature of the gas produced by the burning of sulfur be tested?
Answer: Add a small quantity of water to the tumbler, shake it well, and test the solution with red and blue litmus paper.
32) What is the nature of the oxide formed when magnesium is burned?
Answer: Basic.
33) How can the acidic/basic nature of an oxide be tested?
Answer: By dissolving it in water and testing the solution with litmus paper.
34) What is the general nature of metallic oxides?
Answer: Basic.
35) What is the general reaction of metals with acids?
Answer: Most metals react with acids to produce hydrogen gas.
36) How is the presence of hydrogen gas detected?
Answer: Bring a burning matchstick near the mouth of the test tube and listen for a "pop" sound.
37) What is the general reaction of non-metals with acids?
Answer: Non-metals are generally unreactive with acids.
38) Are there any differences in the reactivity of different metals with acids?
Answer: Yes, some metals are more reactive than others. For example, magnesium and aluminum may react more vigorously than iron or copper.
39) What factors can influence the reactivity of metals with acids?
Answer: The nature of the metal, the concentration of the acid, and the temperature.
40) How does copper react with dilute hydrochloric acid and dilute sulfuric acid?
Answer: Copper does not react with dilute hydrochloric acid but reacts with dilute sulfuric acid.
41) What happens when sodium hydroxide is added to aluminum foil?
Answer: A reaction occurs, and hydrogen gas is produced (indicated by the "pop" sound).
42) Do non-metals generally react with bases?
Answer: Reactions of non-metals with bases are complex and not as straightforward as those with metals.
43) What is a displacement reaction?
Answer: A reaction in which a more reactive metal displaces a less reactive metal from its compound.
44) What are the reactants and products in the reaction between copper sulfate and zinc metal?
Answer: Reactants: Copper sulfate (CuSO₄), Zinc (Zn); Products: Zinc sulfate (ZnSO₄), Copper (Cu).
45) What are the reactants and products in the reaction between iron sulfate and copper turnings?
Answer: Reactants: Iron sulfate (FeSO₄), Copper (Cu); Products: No reaction occurs.
46) What does the "pop" sound indicate in these reactions?
Answer: The presence of hydrogen gas.
47) Can you summarize the reactivity of metals and non-metals with acids and bases based on the given experiments?
Answer: Metals: Most metals react with acids to produce hydrogen gas. Their reactivity with bases can vary.
Non-metals: Non-metals generally do not react with acids. Their reactions with bases can be complex.
Displacement reactions: More reactive metals can displace less reactive metals from their compounds.
48) Why is zinc able to displace copper from copper sulfate, but copper cannot displace zinc from zinc sulfate?
Answer: Zinc is more reactive than copper. A more reactive metal can displace a less reactive one, but not vice versa.
49) What is the order of reactivity of zinc, iron, and copper?
Answer: Zinc > Iron > Copper (Zinc is most reactive, copper is least reactive).
50) Why are metals used in various applications like machinery, automobiles, and cooking utensils?
Answer: Metals possess properties like strength, durability, and malleability that make them suitable for these applications.
51) Name some non-metals and their uses.
Answer: Oxygen: Essential for life, used in breathing.
Nitrogen: Used in fertilizers.
Chlorine: Used in water purification.
Sulfur: Used in various industrial applications.
Carbon: Used in crackers and other products.
Phosphorus: Used in fertilizers and matches.
52) What is an element?
Answer: A substance that cannot be broken down into simpler substances by chemical
53) What is the smallest unit of an element?
Answer: An atom.
54) How do elements differ from compounds?
Answer: Elements consist of only one type of atom, while compounds are composed of multiple types of atoms chemically combined.
55) Can elements be broken down by physical changes?
Answer: No, the atoms of an element remain unaffected by physical changes.
56) How many naturally occurring elements are there?
Answer: Less than 92.
57) What are the three main categories of elements?
Answer: Metals, non-metals, and metalloids.
58) What are metalloids and their characteristics?
Answer: Metalloids are elements that exhibit properties of both metals and non-metals. They may have a metallic luster but are brittle and semiconductors.
60) In what form is magnesium found in plants?
Answer: Magnesium is found in plants primarily as a component of chlorophyll.
61) Where is iron found in the human body?
Answer: Iron in the human body is primarily found in two forms: Hemoglobin and Myoglobin.
62) When sulfur dioxide is dissolved in water which acid is formed?
Answer: Sulphurous acid.
63) Generally what is the nature of the oxides of non-metals?
Answer: Acidic in nature.
