Metals and their compounds

Question 1

What are the general properties of metals?

Answer 1

Metals are generally good conductors of heat and electricity, have high melting and boiling points, are malleable, ductile, and have a shiny appearance (metallic luster).

Question 2

How is sodium hydroxide produced?

Answer 2

Sodium hydroxide is produced by the electrolysis of brine (concentrated sodium chloride solution)

Question 3

What are the uses of sodium hydroxide?

Answer 3

Sodium hydroxide is used in the manufacture of soap, paper, and synthetic fibers, and in the precipitation of metallic hydroxides.

Question 3

What is the action of sodium hydroxide on aluminum, zinc, and lead ions?

Answer 3

Sodium hydroxide reacts with aluminum, zinc, and lead ions to form their respective hydroxides, which are insoluble in water and precipitate out of solution.

Question 4

How is sodium trioxocarbonate (IV) produced?

Answer 4

Sodium trioxocarbonate (IV) is produced by the Solvay process, which involves the reaction of sodium chloride, ammonia, and carbon dioxide.

Question 5

What are the uses of sodium trioxocarbonate (IV)?

Answer 5

Sodium trioxocarbonate (IV) is used in the manufacture of glass, detergents, and as a water softener.

Question 6

What is the economic importance of seawater?

Answer 6

Seawater is an important source of sodium chloride, magnesium, and other minerals.

Question 6

How is sodium chloride recovered from seawater?

Answer 6

Sodium chloride is recovered from seawater by evaporating the water, leaving behind the salt.

Question 7

How is calcium oxide prepared from seashells?

Answer 7

Calcium oxide is prepared by heating seashells (calcium carbonate) in a kiln, which decomposes them into calcium oxide and carbon dioxide.

Question 8

What are the uses of calcium oxide?

Answer 8

Calcium oxide is used in the manufacture of cement, as a flux in steelmaking, and in the treatment of acidic soils.

Question 9

What is the test for calcium ions (Ca²⁺)?

Answer 9

Calcium ions can be tested by adding ammonium oxalate, which forms a white precipitate of calcium oxalate.

Question 10

What is the chemical composition of cement?

Answer 10

Cement is composed of calcium oxide, silicon dioxide, aluminum oxide, and iron oxide.

Question 11

How is bauxite purified?

Answer 11

Bauxite is purified by the Bayer process, which involves treating it with sodium hydroxide to dissolve the aluminum oxide, leaving behind impurities.

Question 12

How is aluminum extracted electrolytically?

Answer 12

A: Aluminum is extracted by the electrolysis of molten alumina (aluminum oxide) dissolved in cryolite.

Question 13

What are the uses of aluminum?

Answer 13

Aluminum is used in the manufacture of aircraft, kitchen utensils, electrical cables, and packaging materials.

Question 14

What is the test for aluminum ions (Al³⁺)?

Answer 14

Aluminum ions can be tested by adding sodium hydroxide, which forms a white precipitate of aluminum hydroxide that dissolves in excess sodium hydroxide to form a clear solution.

Question 15

How is tin extracted from its ores?

Answer 15

Tin is extracted from its ores by roasting the ore to remove sulfur, followed by smelting in a furnace with carbon.

Question 16

What are the uses of tin?

Answer 16

Tin is used in the manufacture of tinplate for food containers, in soldering, and in alloys such as bronze.

Question 17

What are the characteristic properties of the first transition series metals?

Answer 17

The first transition series metals have variable oxidation states, form colored compounds, can form complex ions, and often act as catalysts.

Question 18

What is the significance of the electron configuration of transition metals?

Answer 18

The electron configuration of transition metals allows them to have variable oxidation states and form various types of chemical bonds.

Question 19

How is iron extracted from its ores?

Answer 19

Iron is extracted from its ores by heating with carbon in a blast furnace, where iron oxide is reduced to iron.

Question 20

What is the role of transition metals in catalysis?

Answer 20

Transition metals can act as catalysts due to their ability to change oxidation states and provide a surface for reactions to occur.

Question 21

What are the different forms of iron?

Answer 21

The different forms of iron include cast iron, wrought iron, and steel, each with varying amounts of carbon and different properties.

Question 22

What is the test for iron(III) ions (Fe³⁺)?

Answer 22

Iron(III) ions can be tested by adding potassium thiocyanate, which forms a blood-red solution.

Question 22

What is the test for iron(II) ions (Fe²⁺)?

Answer 22

Iron(II) ions can be tested by adding potassium hexacyanoferrate(III), which forms a pale blue precipitate.

Question 23

How is copper extracted from its ores?

Answer 23

Copper is extracted from its ores by roasting the ore to convert sulfides to oxides, followed by reduction with carbon or electrolysis

Question 24

How is copper(II) tetraoxosulphate(VI) prepared?

Answer 24

Copper(II) tetraoxosulphate(VI) (CuSO₄) is prepared by reacting copper oxide with sulfuric acid.

Question 24

What are the uses of copper?

Answer 24

Copper is used in electrical wiring, plumbing, and the manufacture of alloys like bronze and brass.

Question 25

What is the test for copper(II) ions (Cu²⁺)?

Answer 25

Copper(II) ions can be tested by adding sodium hydroxide, which forms a blue precipitate of copper(II) hydroxide.

Question 26

What are the constituents and uses of steel?

Answer 26

Steel is an alloy of iron and carbon, used in construction, tools, and machinery.

Question 27

What are the constituents and uses of stainless steel?

Answer 27

Stainless steel is an alloy of iron, chromium, and nickel, used in cutlery, kitchenware, and medical instruments.

Question 28

What are the constituents and uses of brass?

Answer 28

Brass is an alloy of copper and zinc, used in musical instruments, plumbing, and decorative items.

Question 29

What are the constituents and uses of bronze?

Answer 29

Bronze is an alloy of copper and tin, used in sculptures, medals, and bearings.

Question 30

What are the constituents and uses of duralumin?

Answer 30

Duralumin is an alloy of aluminum, copper, manganese, and magnesium, used in aircraft construction.

Question 31

What are the properties and uses of alloys compared to pure metals?

Answer 31

Alloys generally have improved strength, corrosion resistance, and hardness compared to pure metals, making them more suitable for specific applications.