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Define the following terms. (i) Mineral (ii) Ore (iii) Gangue
Mineral: A mineral is an element or compound that occurs naturally in the earth's crust. It is characterized by its chemical composition and physical properties. Minerals can be found in various forms and are often extracted for their valuable metals or compounds. Ore: An ore is a type of mineral thRead more
Mineral: A mineral is an element or compound that occurs naturally in the earth’s crust. It is characterized by its chemical composition and physical properties. Minerals can be found in various forms and are often extracted for their valuable metals or compounds.
Ore: An ore is a type of mineral that contains a high concentration of a particular metal or metals, making it economically viable to extract the metal(s) from it. Ores are typically mined from the earth and undergo various processes to separate the desired metal(s) from the other components.
Gangue: Gangue refers to the impurities or unwanted substances that are present in an ore. These impurities can include soil, sand, rocks, and other non-valuable minerals. Gangue needs to be removed from the ore before the extraction of the metal can take place.
See lessWhy do ionic compounds have high melting points?
Ionic compounds have high melting points due to the strong force of attraction between the positive and negative ions. This force of attraction, known as electrostatic attraction, requires a considerable amount of energy to break. As a result, a significant amount of heat is needed to overcome thisRead more
Ionic compounds have high melting points due to the strong force of attraction between the positive and negative ions. This force of attraction, known as electrostatic attraction, requires a considerable amount of energy to break. As a result, a significant amount of heat is needed to overcome this force and convert the solid ionic compound into a liquid state. Therefore, ionic compounds generally have high melting points.
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See less(i) Write the electron-dot structures for sodium and oxygen. (ii) Show the formation of Na2O and MgO by the transfer of electrons. (iii) What are the ions present in these compounds?
The electron-dot structure for sodium (Na) is represented as Na•, where the dot represents the valence electron. The electron-dot structure for oxygen (O) is represented as •O•, where each dot represents a valence electron. Formation of Na2O and MgO by the transfer of electrons: Na2O is formed by thRead more
The electron-dot structure for sodium (Na) is represented as Na•, where the dot represents the valence electron.
The electron-dot structure for oxygen (O) is represented as •O•, where each dot represents a valence electron.
Formation of Na2O and MgO by the transfer of electrons:
Na2O is formed by the transfer of electrons from sodium (Na) to oxygen (O). Each sodium atom donates one electron to oxygen, resulting in the formation of two sodium cations (Na+) and one oxygen anion (O2-). The resulting compound is Na2O.
MgO is formed in a similar manner. Magnesium (Mg) donates two electrons to oxygen, resulting in the formation of one magnesium cation (Mg2+) and one oxygen anion (O2-). The resulting compound is MgO.
Ions present in Na2O and MgO:
In Na2O, the ions present are two sodium cations (Na+) and one oxygen anion (O2-).
In MgO, the ions present are one magnesium cation (Mg2+) and one oxygen anion (O2-).
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See lessp. 13
What would you observe when zinc is added to a solution of iron (II) sulphate? Write the chemical reaction that takes place.
When zinc is added to a solution of iron (II) sulphate, you would observe a displacement reaction. The zinc metal will displace the iron from the iron (II) sulphate solution, resulting in the formation of zinc sulphate and iron metal. The chemical reaction can be represented as follows: Zn + FeSO4 -Read more
When zinc is added to a solution of iron (II) sulphate, you would observe a displacement reaction. The zinc metal will displace the iron from the iron (II) sulphate solution, resulting in the formation of zinc sulphate and iron metal. The chemical reaction can be represented as follows:
Zn + FeSO4 -> ZnSO4 + Fe
In this reaction, the zinc metal replaces the iron in the compound, leading to the formation of zinc sulphate and the liberation of iron metal.
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See lessWhich gas is produced when dilute hydrochloric acid is added to a reactive metal? Write the chemical reaction when iron reacts with dilute H2SO4.
When dilute hydrochloric acid is added to a reactive metal, hydrogen gas is produced. This is because the acid reacts with the metal to form a salt and hydrogen gas. The general chemical equation for this reaction is: Metal + Dilute acid → Salt + Hydrogen. When iron reacts with dilute sulfuric acidRead more
When dilute hydrochloric acid is added to a reactive metal, hydrogen gas is produced. This is because the acid reacts with the metal to form a salt and hydrogen gas. The general chemical equation for this reaction is: Metal + Dilute acid → Salt + Hydrogen.
When iron reacts with dilute sulfuric acid (H2SO4), iron sulfate (FeSO4) and hydrogen gas (H2) are produced. The chemical equation for this reaction is: Fe + H2SO4 → FeSO4 + H2.
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See lessp. 7
Write equations for the reactions of (i) iron with steam (ii) calcium and potassium with water
Reactions of Iron with Steam: When iron reacts with steam, it forms iron(III) oxide and hydrogen gas. The chemical equation for this reaction is: 3Fe(s) + 4H2O(g) → Fe3O4(s) + 4H2(g) Reactions of Calcium and Potassium with Water: When calcium reacts with water, it forms calcium hydroxide and hydrogeRead more
Reactions of Iron with Steam:
When iron reacts with steam, it forms iron(III) oxide and hydrogen gas. The chemical equation for this reaction is:
3Fe(s) + 4H2O(g) → Fe3O4(s) + 4H2(g)
Reactions of Calcium and Potassium with Water:
When calcium reacts with water, it forms calcium hydroxide and hydrogen gas. The chemical equation for this reaction is:
Ca(s) + 2H2O(l) → Ca(OH)2(aq) + H2(g)
When potassium reacts with water, it forms potassium hydroxide and hydrogen gas. The chemical equation for this reaction is:
2K(s) + 2H2O(l) → 2KOH(aq) + H2(g)
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Why is sodium kept immersed in kerosene oil?
Sodium is kept immersed in kerosene oil because it reacts vigorously with air and water. Kerosene oil acts as a protective layer, preventing sodium from coming into contact with air and moisture, which could lead to a dangerous reaction. By keeping sodium immersed in kerosene oil, it remains stableRead more
Sodium is kept immersed in kerosene oil because it reacts vigorously with air and water. Kerosene oil acts as a protective layer, preventing sodium from coming into contact with air and moisture, which could lead to a dangerous reaction. By keeping sodium immersed in kerosene oil, it remains stable and can be safely stored and handled.
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See lessp. 6
Explain the meanings of malleable and ductile.
Malleability refers to the property of a metal to be beaten into thin sheets without breaking or cracking. It allows metals to be shaped and formed into various structures or objects. Gold and silver are examples of metals that are highly malleable. Ductility refers to the property of a metal to beRead more
Malleability refers to the property of a metal to be beaten into thin sheets without breaking or cracking. It allows metals to be shaped and formed into various structures or objects. Gold and silver are examples of metals that are highly malleable.
Ductility refers to the property of a metal to be drawn into thin wires without breaking or fracturing. It allows metals to be stretched and formed into long, thin strands. Gold is the most ductile metal, and a wire of about 2 km length can be drawn from just one gram of gold.
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1. Give an example of a metal which (i) Is a liquid at room temperature? (ii) Can be easily cut with a knife? (iii) Is the best conductor of heat? (iv) Is a poor conductor of heat?
Examples of Metals (i) A metal that is a liquid at room temperature is mercury. (ii) A metal that can be easily cut with a knife is sodium. (iii) The best conductor of heat among metals is silver. (iv) A poor conductor of heat among metals is lead.
Examples of Metals
(i) A metal that is a liquid at room temperature is mercury.
(ii) A metal that can be easily cut with a knife is sodium.
(iii) The best conductor of heat among metals is silver.
(iv) A poor conductor of heat among metals is lead.
See lessWhich metal compound reacts with dilute hydrochloric acid to produce the gas evolved extinguishes a burning candle?
The metal compound that reacts with dilute hydrochloric acid to produce a gas that can extinguish a burning candle is calcium carbonate (CaCO3). When calcium carbonate reacts with dilute hydrochloric acid (HCl), it produces calcium chloride (CaCl2), water (H2O), and carbon dioxide gas (CO2). The carRead more
The metal compound that reacts with dilute hydrochloric acid to produce a gas that can extinguish a burning candle is calcium carbonate (CaCO3). When calcium carbonate reacts with dilute hydrochloric acid (HCl), it produces calcium chloride (CaCl2), water (H2O), and carbon dioxide gas (CO2). The carbon dioxide gas can extinguish a burning candle because it displaces oxygen and reduces the oxygen concentration in the vicinity of the flame, leading to the extinguishing of the flame. Here’s the balanced chemical equation for the reaction:
CaCO3 + 2HCl -> CaCl2 + H2O + CO2
So, in this reaction, it’s the carbon dioxide (CO2) gas evolved that can extinguish a burning candle.
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